Since the emergence of FORTRAN in 1957, the programming lexicon has evolved drastically. There are hundreds of programming languages used to interact with a computer system — according to Wikipedia, the number is 700!. The popularity of coding languages depends on the number of people using them and their Turing-completeness.
The world of coding is inexplicably vast and rapidly growing, making software development one of the most sought-after careers. That also makes software programming a highly competitive field that demands you to have competence in more than one language to attract job offers from Facebook, Amazon, Apple, Netflix, and Google, popularly called FAANG.
So, how do you decide which language to select and master for your tech interviews at these top-tier tech companies? You can choose them based on the:
- Scope and job opportunities
- Your learning goals
- Salary bands
- Programming languages used by software developers in FAANG
Based on these factors, we’ve narrowed down the 10 most popular programming languages that you can pick from while preparing for your coding interviews at FAANG and other large tech companies.
Top 10 Most Popular Programming Languages Used by FAANG
If you are learning a new language but are confused about which ones to select, this list will prove to be a good starting point. How will this list help you crack tech interviews at tech giants?
Learning about these languages, their functions, and the door of opportunities each one can open for you and then mapping them with your interests, curiosities, and career goals will give you the right direction for your technical interview prep!
So, here’s our list of the 10 most popular coding languages you should consider learning in 2021.
Released in: 1991
Career opportunities: Very high
Average base salary: $108,602 per year (as of June 2021)
Current number of jobs: 40,026 (as of June 2021)
As one of the most popular coding languages globally, Python finds invaluable use in solving problems and gaining insights. The language has recorded a 27% year-over-year user growth, mainly fueled by data analysts and data scientists.
Its application in AI analysis, deep learning, and data analysis is indispensable. Python is definitely among the top 3 popular programming languages of 2021.
Job Prospects in Python
Since Python is a general-purpose language, it offers a lot more versatility in job designations than its contemporaries do. So, learning Python will bring you abundant career opportunities. From entry-level software developers with an average annual salary of $86,868 to Machine Learning Engineers earning $151,373, the scope of Python-based jobs is invariably broad.
Why Should You Learn Python?
- Python is a general-purpose, high-level, interpreted language known for its ease of use, extensive libraries and tools, and code readability.
- Python can handle complex algorithms and is excellent for data automation, making it a natural fit for machine learning.
- Being open-source, it has support from a large community of Python users committed to making it better and more efficient.
- Python has several mobile and web development frameworks like Django, TurboGears, Bottle, Pyramid, and Flask, as well as scientific application frameworks like TensorFlow, Keras, and SciPy.
- Software engineers use Python to develop GUI-based applications, handle AI computations, and information science.
- Python’s database access layers are comparatively underdeveloped. This is in reference to JDBC and ODBC.
- Python doesn't find much use in client-side scripting.
- Python is somewhat restricted when it comes to design because it’s dynamically typed.
Top Companies Using Python
Python's prominence at Google is a much-talked-about subject amongst coding engineers. The company works on a hard-line philosophy that states, "Python where we can, C++ where we must."
Google deems Python to be extremely readable, easy to use and maintain, and a good interface to C++ libraries. It is the official server-side scripting language at the company alongside C++, Go, and Java. Therefore, Python developers are always in demand at Google.
In the words of the Director of Search Quality at Google, Peter Norvig:
“Python has been an important part of Google since the beginning and remains so as the system grows and evolves. Today, dozens of Google engineers use Python, and we’re looking for more people with skills in this language.”
Netflix's usage of Python involves server-side data analysis. It also uses Python alongside its monkey applications to monitor security policies, alerts, SSL certificates, and search history.
Netflix offers software developers the option to pick the programming language they wish to code in. The data in recent years has indicated an increase in Python-based applications, thereby driving the demand for Python developers. Python's rich libraries, large community support, and ease of usage are the primary factors driving its widespread popularity.
Python has a considerable contribution to the efficiency of Facebook services, which has allowed the social media giant to scale its infrastructure. Production engineers use Python for binary distribution, infrastructure management, automating services and utilities, and hardware imaging.
Python is currently among the top 3 most popular programming languages at Facebook alongside C++ and Hack (PHP dialect). There are several Python projects published by Facebook, including the Python Async IRCbot framework currently being used to upgrade Facebook infrastructure.
Among other companies that extensively rely on Python are Spotify, Instagram, Dropbox, Reddit, and Quora.
Released in: 1996
Career opportunities: Very high
Average base salary: $102,775 per year (as of June 2021)
Current number of jobs: 54,491 (as of June 2021)
Even after 30 years of its release by Sun Microsystems, Java is still one of the most used and in-demand programming languages today. Oracle eventually took over Java. Java shares similarities with C++ and C#, making it easier to branch into different programming domains with knowledge of just one of them.
It is used to develop mobile applications, gaming consoles, and software applications based on databases. With 10.45% ratings, Java is featured on the #3 position on the TIOBE index of the most popular programming languages of 2021.
Job Prospects in Java
Java developers are perpetually in demand and can expect to earn six-figure salaries depending on their experience, competence, and job location. The average salary range for a Java developer is between $51k to 1067k per year. When combined with Scala, this can mean a 66% salary hike.
Why Should You Learn Java?
- Java follows the “Write Once, Run Anywhere” principle, which means that it is platform-independent. Java programs created on one operating system can run on any other operating system supporting Java Virtual Machine.
- Java is an OOP language that allows code reusability, data abstraction, and easy maintenance.
- Java's syntax is simple and easy to understand. Even though it’s less beginner-friendly than Python, it has a mild learning curve that makes learning C# and C++ easier.
- Other useful features of Java include automatic memory management, multithreading, and Remote Method Invocation (RMI).
- Java's use cases range from e-commerce sites, laptops, gaming consoles, mobile devices, and complex web and mobile applications. It is used to design dynamic design elements such as drop-down menus, animated images, etc.
- Java's memory management using garbage collection can result in poor performance if a program exceeds 20% of CPU time.
- Since Java code is interpreted at runtime, it is slower when compared with C or C++.
- It’s slightly complex to code when compared with other high-level languages like Python.
Top Companies Using Java
Numerous Android applications are written using Java. Google's Gmail and Web Toolkit are also developed using Java. Consequently, there is always a demand for Java developers at Google. There are currently 1.9k job openings at various locations at Google that list Java as a core skill.
Twitter, which was created on Ruby on Rails, switched to Java to handle copious amounts of traffic. During the early 2010s, the social media giant unlocked the potential of Java Virtual Machine and has continued to leverage the language ever since.
Even though the streaming giant allows developers to opt for tools and languages of their choice, Java has always been an integral part of Netflix in back-end development. It uses Spring Boot for its Services Oriented Architecture (SOA).
Since Java finds tremendous use in services that need to be scaled, it is the top choice of tech giants like Google, Square, Instagram, eBay, Amazon, Airbnb, and Google, among others.
It is also used for application development by cloud computing service providers like Microsoft, Amazon, and Google.
Released in: 1995
Career opportunities: Very high
Average base salary: $111,867 per year (as of June 2021)
Current number of jobs: 48,583 (as of June 2021)
Released in: 1972
Career opportunities: High
Average base salary: $100,631 per year (as of June 2021)
Current number of jobs: 16,208 (as of June 2021)
C is positioned at #1 with 13.83% ratings, followed by Python, Java, and C++. C, Python, and Java make for a good combination of languages to build a solid coding foundation. Being developed in the 70s, C forms the basis of many new languages such as Python and Ruby.
Job Prospects in C
Considering how long ago C was released, the current demand for C developers says a lot about the functional benefits of this language. Being good at C will open plenty of pathways as the use cases of this language expand far and wide. C is mainly used in embedded systems, but it’s also used in network drivers, databases, assemblers, OS, language compilers, and more.
The salary band of C developers is right up there alongside the other popular languages on this list, with an average base salary of around $100K for software engineers.
Why Should You Learn C?
- C has a wide range of industry use cases, including medical devices in healthcare, automobiles, robotics, AI, ML, etc.
- C is easy to test, debug, and maintain.
- It can run on any type of device.
- It forms the foundation of many modern languages, making it easier for you to learn them.
- The syntax of C language is more complex as compared to modern languages.
- C is quite old for new and modern use cases such as websites and mobile applications.
Top Companies Using C
The kernel of Microsoft Windows is largely developed using C, with some parts written in assembly language. This means the operating system that's the most widely used one across the globe is run by C. Another powerful OS, Linux, is also developed in C. Android kernels too are written in C.
Apple’s Mac computers have their SS X kernel written in C programming language.
Adobe Photoshop, Premiere, and many other applications by Adobe were all created using C.
Most popular databases, including Oracle Database, MySQL, PostgreSQL, use C as their coding language.
Google’s Chromium browser is developed using C. C programming language is also used in IoT applications.
Released in: 1985
Career opportunities: High
Average base salary: $113,137 per year (as of June 2021)
Current number of jobs: 14,914 (as of June 2021)
C++ or "C with Classes" is a general-purpose, object-oriented programming language created as an extension to C. Even though different in many respects, both languages are used for designing operating systems, browsers, games, and web applications. They have contributed to developing programming languages like C#, Java, PHP, and Verilog.
Job Prospects in C++
C++ is the language of choice of roboticists, gaming developers, as well as avionics programmers. To land a job at top companies like Tesla and NVIDIA, one must consider learning "low-level" programming languages like C and C++. Since Google's culture is shaped by C/C++, and Microsoft has plenty of its services written using these languages, it's a good idea to learn C/C++ before interviewing at Google and Microsoft.
The average salary of a C++ developer is over $113K per year. Close to 15,000 jobs are listed on Indeed for C++ programmers. In recent years, there has been an increase in the remuneration of C++ developers who demonstrate competence in Agile methodologies.
Why Should You Learn C++?
- C++ is a powerful, high-performance language that large-scale companies use to deliver complex applications.
- C++ codes are highly portable
- It comprises standard libraries that allow users to build network applications
- Pointers in C++ can result in system failures if not used rightly. They also make C++ programs vulnerable to security concerns.
- C++ doesn't support automatic memory management like Python and Java.
Top Companies Using C++
As we mentioned before, Google runs on a strict "Python where we can, C++ where we must" policy. When it comes to complex applications, C++ is more of a necessity than an option.
Microsoft's Windows OS is majorly written using C++. Microsoft Office and Internet Explorer also have extensive use of C++.
Facebook and Amazon also use C++ for low-level infrastructure development. Evernote, Opera, and NASA are among other top companies using C++. Other applications are Mozilla Firefox and Thunderbird.
Released in: 2009
Career opportunities: High
Salary band: $104,331 to $148,538 per year (as of June 2021)
Current number of jobs: 9,342 (as of June 2021)
Go or Golang is an open-source language developed by Google. In recent years, it has surpassed the likes of Ruby and is fast becoming the server language of choice for web developers. Golang registered an 8% growth between Q3 2019 to Q4 2019. Golang is known for its simplicity, enhanced security, improved efficiency, and code readability.
Job Prospects in Go
As per the 2020 Stack Overflow survey, Golang is amongst the highest-paying programming languages. According to a survey conducted by Go, around 76% of the respondents admit to using Go at work, and 66% said that the language is critical to their company’s success.
“Go will be the server language of the future.” — CEO of Shopify Tobias Lütke
Why Should You Learn Go?
- Golang supports multithreading, which is further made simpler due to its lightweight nature and quick execution.
- Golang eliminates virtual machine dependencies. Its code is not dependent on classes and constructors.
- Go supports object-oriented programming.
- Golang is feature-rich and relatively functional due to its short compilation time. It consists of a collection of libraries and packages to enhance its performance.
- Majority of programmers using Go feel extremely productive in less than three months of using it.
- Go is not suitable for complex applications since it’s deliberately limited to enhance simplicity in use.
- Since Go is relatively new, it doesn't comprise many syntax libraries that can reduce coding time.
Top Companies Using Go
Being a product of Google, Go is employed in several internal projects at the company. Among its applications are Google Chrome, Google App Engine, and Google Earth. Go has been used by YouTube since 2011.
Go is employed in heavy-loaded systems of Twitch. It enables simultaneous streaming of live video and chats.
Uber uses Golang for its geofence service. This service implements dynamic pricing by considering special requirements of an area, improving Uber’s functionality of matching user location with product availability.
SoundCloud uses Go with Ruby Rails to conduct real-time static analysis.
Other big companies that use Go are Dropbox, Dailymotion, and Uber.
Released in: 2010
Career opportunities: High
Average base salary: $100,357 per year (as of June 2021)
Current number of jobs: 45,830 (as of June 2021)
Kotlin is a powerful, open-source programming language developed by JetBrains (Amazon Partner Network Technology partners) that supports Android and iOS mobile platforms. It is often considered a JVM-based alternative to Java.
Even though Kotlin code cannot be integrated with Java, it can interoperate with Java to produce code that can run on JVM. It is a statically typed language that, despite having been released in 2010, has garnered a large community of developers since Google announced its support for Kotlin in 2017.
Job Prospects in Kotlin
Since Google announced its support for Kotlin-first development of Android applications, there has been a steady rise in job opportunities for Kotlin developers. A simple search on LinkedIn would reveal over 45,000 jobs listed for Kotlin as a skill. With Google’s backing, Kotlin developers can find plenty of high-paying job opportunities to pursue, and it’s one of the most popular programming languages today.
Why Should You Learn Kotlin?
- Kotlin is easy to maintain due to its fault-proof nature.
- Kotlin is intuitive and easy to read, which makes writing code faster.
- Kotlin supports interoperability with all Java tools and frameworks; Kotlin code can easily be migrated to Java.
- Kotlin is compatible with development tools like Spring, JetBrains, Gradle, Spark Java, and Codename One, among others.
- Kotlin is slower in comparison to Java when it comes to clean builds.
- Since Kotlin is relatively new, there aren't sufficient learning resources to master the language.
Top Companies Using Kotlin
Google's primary reason for choosing Kotlin is the fewer blocks of code it requires, thus, preventing boilerplate issues. Nearly 50% of Android developers are users of Kotlin. Google also announced Jetpack Compose, a Kotlin-first reactive UI library associated with the Android Open Source Project (AOSP), to encourage developers to use Kotlin to develop Android apps.
Kotlin is used by Amazon's cloud computing platform — Amazon Web Services (AWS), for deploying server-side applications to hosts that support Java applications.
Other top companies that use Kotlin are Netflix, Foursquare, Basecamp, Capital One, Coursera, Uber, and Pinterest.
Released in: 2014
Career opportunities: High
Average base salary: $105,526 per year (as of June 2021)
Current number of jobs: 2,473 (as of June 2021)
Developed by Apple in 2014, Swift is a highly performative language used to create iOS applications and programming iOS-based devices like WatchOS, MacOS, iPadOS, and tvOS. Apple claims it to be 2.6 times faster than the old Objective-C.
Job Prospects in Swift
With the backing of Apple, Swift is well-positioned to dominate iOS development in the coming years. In just the short time since its release, Swift has already garnered a large community of developers. Therefore, the demand for Swift developers is only expected to grow.
The average salary of Swift developers stands at a little over $100K as per PayScale. According to Stack Overflow, Swift is the sixth most loved programming language. Swift offers you an opportunity to earn more with relatively less experience than Objective-C, its predecessor.
Why Should You Learn Swift?
- Swift code is concise and expressive, which makes it easy to read and maintain. It also requires fewer lines of code to perform the same task as Objective-C.
- Swift is highly efficient in handling errors such as system failures and bugs. It is also faster, safer, and less time-consuming.
- Since Apple backs Swift as its language of choice over Objective-C, it is future-proof and opens doors for scalability.
- Swift can be integrated with Objective-C easily and is compatible with the Linux operating system.
- Since Swift is relatively new, it still suffers from certain issues like a lack of backward compatibility. Updated versions sometimes don’t support features of the previous versions, often causing developers to rewrite code.
- Swift could benefit from skilled developers to aid in the progress of the language. Currently, at the rate the language is growing, a talent gap is imminent.
Top Companies Using Swift
Apple's IDE (Integrated Development Environment) supports both macOS and iOS apps. Of the nearly 500,000 iOS apps on Apple Store, a significant number of popular apps are powered by Swift, which includes Khan Academy, Uber, Square, Lyft, and Airbnb. Most new iOS apps today are created using Apple.
WhatsApp (which is now a part of Facebook) utilizes the high performance and extensive functionality of Swift.
When Uber switched to Swift, it cited reliability issues and inconsistency in architecture to be the reason for quitting C-Objective. Now, Swift is Uber's primary app development language ensuring swift functionality and seamless performance of its iOS app.
Other big companies that use Swift are LinkedIn, Coursera, Pandora, Twitter, Vimeo, and Groupon.
Released in: 2000
Career opportunities: High
Average base salary: $94,775 (as of June 2021)
Current number of jobs: 32,606 (as of June 2021)
Created by the tech giant Microsoft, C# began its journey with the criticism of being a duplicate of Java. However, in the last 20 years, the language has evolved to earn its own identity. It has become a scalable, multi-paradigm language capable of running on Windows, Linux, iOS, and Android-powered systems.
TIOBE ranked C# as the 5th most popular language in its 2021 index, which is the same position the coding language held last year, with its popularity continuing its upward trend.
Job Prospects in C#
With over 32K current postings for C# Developers on Indeed, the job opportunities offered by this programming language are pretty high and diverse owing to its versatile applications. The average salary is promising, too, making it inevitable for us to include C# on this list.
Why Should You Learn C#?
- As an object-oriented language, C# is a faster successor of C (it’s pronounced as C Sharp for a reason) and offers improved security with its type-safe feature.
- It is fully integrated with Microsoft’s framework for software applications called .NET, making it compatible for the development of Windows and mobile applications.
- It has a rich collection of libraries and frameworks with many inbuilt functions that contribute to its high execution and overall development speed.
- Built with the best features of Java and C++, a programmer with experience in C or C++ can easily get comfortable with C#.
- Based on the Microsoft .NET framework, C# offers less flexibility.
- Some argue the learning curve of C# might be steep, and it’s not easy to make changes to your C# code, as it requires it to be compiled first.
Top Companies Using C#
Built by Microsoft, it’s a no-brainer that C# is the tech giant’s most preferred language to use to build software for Windows applications. C# is used to build cross-platform apps on Xamarin.
C# is also the go-to language to build 2D and 3D games. With its seamless integration with the Unity game engine — the engine used to build more than one-third of the top games, C#’s contribution to game development is enormous.
Accenture, Intuit, GrubHub, StackOverflow, and Stack Exchange are other companies that use C# in their tech stack.
Released in: 1994
Career opportunities: High
Average base salary: $89,890 (as of June 2021)
Current number of jobs: 7,517 (as of June 2021)
One of the oldest and the most widely used server-side web development language, PHP (Hypertext Preprocessor), is ranked 9th in TIOBE Index for May 2021. Despite being around for more than 20 years, the language is still going strong as one of the most popular programming languages. It is the preferred language for many developers and leading tech companies.
Some of the most popular PHP frameworks you must be aware of are CodeIgniter, Laravel, and Sumfony. PHP is one of the most in-demand languages of 2021 and the one you should consider learning if you wish to crack tech interviews at FAANG and other top companies.
Job Prospects in PHP
Although PHP is not as popular as it used to be (due to the development and popularity of newer and other alternatives), the job opportunities for PHP are good, with over 7000 openings on Indeed. The salary band for a PHP Developer is close to those of C# and Kotlin.
Why Should You Learn PHP?
- PHP is a beginner-friendly language, and the code is easy to bug.
- Having been in use for over two decades, PHP has rich resources in the form of libraries with functional modules such as graphs and PDF and frameworks that reduce coding time.
- PHP frameworks allow working with different relational databases.
- PHP’s extensive collection of automation tools makes it an easy-to-use language. They help automate common web development tasks, including authentication and session management.
- PHP has security issues and vulnerabilities, making it an unsecure programming language.
- Due to its lack of modular nature, PHP isn’t the best choice for huge applications.
Top Companies Using PHP
One of the biggest industry use cases of PHP is Facebook. Facebook is developed mainly using PHP code.
The world’s largest content-driven site Wikipedia also uses PHP code.
Other companies that use PHP for their computing infrastructure are WordPress, Slack, Mailchimp, Etsy, and Tumblr.
That was our list of the top 10 most popular coding languages that developers of 2021 use. When preparing for your coding interview at FAANG and other tech companies, it would be wise to learn two or more languages from this list to take your coding skills several levels above your peers.
FAQs on FAANG Tech Interview Prep
Question 1. How do I learn about the interview processes at FAANG companies?
Companies often modify their interview processes regularly. Furthermore, tech companies have specific criteria for evaluating candidates. So, make sure you gather information from the HR personnel you are coordinating with, the job description, company website, and other suitable sources before the prep.
The common interview rounds at FAANG include:
- Phone call with a recruiter
- Technical phone interview
- Home assignment
- Onsite interviews
Question 2. How should I build my technical competence to perform well in technical interview rounds?
1. Learn the most used programming languages, frameworks, and databases.
Applicants with proficiency in multiple popular programming languages and the latest programming tools, frameworks, and database systems stand to attract lucrative job prospects from top tech companies like Facebook, Apple, Amazon, Netflix, and Google. To prepare for your interview, gather as much knowledge as possible on the technologies these companies use and the challenges they are currently facing.
The most popular frameworks used by FAANG include ReactJS, Hadoop, NodeJS, Django, Flask, and AngularJS. The most used database technologies, on the other hand, are MySQL, Redis, PostgreSQL, MongoDB, and Cassandra. As for the programming languages, we've already discussed them in detail in this post.
2. Practice the types of questions/problems commonly asked during interviews at FAANG.
Companies usually have a set of questions they ask candidates to test their competence in computer programming. Prepare your answers for as many technical questions as possible. With whiteboard coding questions, you need to build your speed to solve problems faster and more efficiently. For this, you need plenty of practice.
Question 3. How can I test my interview preparation?
Even with the right preparation material, evaluating your interview readiness can be a bit challenging. In that case, you can seek external help. One way to tackle this problem is to sign up for mock interview sessions with someone who has experience and knowledge to help you identify your weaknesses.
This could be experienced hiring managers or technical professionals at FAANG. They could also be someone among your friends and peers. This will also give you a comprehensive insight into the interview process and help overcome anxiety with sufficient rehearsals.
If you’re seeking professional help, Interview Kickstart specializes in mock interviews and many other aspects of interview preparation for FAANG.
To know more about preparing for technical interviews at FAANG and how we can help, register for our free webinar!
Are You Ready to Learn?
It's never easy to start learning something new. However, a clear set of goals and processes will help you significantly get closer to upskilling yourself as a software developer and toward cracking your next coding interview.
Before you decide what programming language(s) you should learn, understand your career goals. Once you do that, analyze your interests and define your learning objectives. That’ll make it easier to select the language that’ll help you gain the skills you seek to get hired for the role you want.
Remember — when it comes to landing your dream job at FAANG or any other top tech company, you need to remain patient and committed to your preparation process, as the interview rounds are quite grueling. Upskill yourself, focusing on the most used programming languages of 2021; this will ensure the career you build is future-proof and rewarding in the long run.
Head over to our blog for more such articles on how to crack technical interviews at FAANG and land your dream job.