Best Programming Languages to Learn in 2021

There's no denying that 2020 was one interesting year for everyone working in the tech industry. The COVID-19 pandemic brought many tech trends to the forefront, while others became marginal or even extinct. Some tools and frameworks got much stronger as the massive communities working on open-source software contributed to them.

So, if you're looking for your next challenge - what programming language should you learn next? 

Here are the best programming languages you should consider learning in 2021. They have a bright future ahead of them, and lots of opportunities will come your way if you master one of them.

1. JavaScript

The most famous popular programming language today, JavaScript is still one of the most sought-after technologies for web development (and beyond). It's a hit among frontend developers but also gaining a foothold in the backend area as well thanks to the NodeJS runtime environment. According to the Stack Overflow 2020 survey, 58% of developers like to work with JavaScript. The language scored the second position in the most wanted technologies among developers.

Popular applications built with JavaScript: Microsoft, PayPal, Google, Groupon. 

Watch our video on why everyone envies JavaScript developers >

Pros of JavaScript

• It runs instantly in the web browser and offers a responsive interface to websites. 
• It's a highly versatile and multipurpose language. You can use it to create web animations, control the web interface, and many others. 
• It’s supported by all modern browsers.
• It's an interpreted language, so it doesn't require so much time for a compilation like other languages (think Java). 
• It's a super popular language, so you'll find lots of JavaScript-related jobs.
• JavaScript has been around for a quarter of a century! This means that plenty of apps were created with it, so it's likely that someone already found a solution to your problem. 
• JavaScript can be used for backend development with the help of NodeJS. 

Cons of JavaScript 

• Security is the biggest problem in using JavaScript because their files are exposed to the webpages. This means that attackers can potentially execute malicious code on the client machine. 
• Since JavaScript is displayed publicly, browser users can potentially control the code written in JavaScript. And other developers can easily download your source code and reuse it. 
• JavaScript also has compatibility issues. In some cases, it might be interpreted differently by the browser.

2. Kotlin

Developed by the JetBrains team to come up with something better than Java, Kotlin has claimed the hearts of many developers over the years. The demand for Kotlin is growing. And the effortless interoperation between Kotlin and Java only makes it more popular among mobile software developers. It was created with the purpose of addressing the major issues that surfaced in Java. 

Popular applications built with Kotlin: Coursera, Uber, Pinterest.

Pros of Kotlin

• It accelerates the development process because it's an incredibly efficient programming language. 
• It comes with a good compiler and provides an improved runtime performance. 
• Kotlin's community is growing fast.

Cons of Kotlin

• It shares many similarities with Java, but mobile app developers still need to learn a lot about Kotlin before jumping on it. 
• Slow compilation speed - Kotlin was made to be faster than Java but keep in mind that in some cases, like clean building, you might encounter slower compilation speed. 
• Kotlin is still not so popular, and you don't find too many people around with high expertise in this language. So, if you encounter a problem, there won't be so many people out there to help you out. 
• Limited resources - learning Kotlin is difficult because there aren't too many learning resources about this relatively programming language yet.

3. Go

Developed by Google in 2007 for APIs and web applications, Go has recently become one of the fastest-growing programming languages. Some programmers consider it as a great alternative to Python and PHP. Go is a great match for minimal web applications, web servers, and APIs. 

Popular apps built with Go: Google, Facebook, Docker, Apple, BBC.

Pros of Go

• The language comes with some really helpful features like memory management, motor data structure support, and high performance. 
• It's versatile, and you can use it for system and network programming, audio and video editing, AI, machine learning, and more. 
• It accelerates the development process. 
• Go has a gentle learning curve and is easy to learn. 
• It scales really well and comes with a set of comprehensive programming tools. 

Cons of Go

• In some cases, Go might turn out to be too simple for your needs. 
• It doesn't include a rich array of smart abstractions that allow developers to achieve complex results with less effort (like other languages). 
• It's still a young technology. It just can't compete with languages like Java that are surrounded by a massive collection of code and lots of new libraries created by its community. Perhaps Go will catch up with its peers, but it still has a long way to run in terms of library support. 
• Go doesn't have a GUI library. It requires a lot of knowledge and time to connect the library to the app instead of using native solutions as you'd do with Java or Python.

4. Swift

First released in 2014 by Apple, Swift is a general-purpose compiled programming language cherished by the open-source community. It's used for all Apple devices. Apart from being powerful and intuitive, Swift helps developers to make writing code simple.

Popular applications built with Swift: Lyft, Uber, Slack. 

Pros of Swift

• Swift code is safe by design, which means that developers commit fewer errors while writing it. 
• Coding in Swift is easy because its syntax is concise but expressive. 
• It helps to develop apps with high performance. 
• It comes with all the modern features that developers love. 
• It's easy to integrate with Objective-C. 
• Its popularity and community support are on the rise. Swift's community is growing fast, even if it's smaller when compared to other open-source languages. 

Cons of Swift

• The technology is still quite young, so it offers a limited number of tools, native libraries, and it might be unstable after a release. 
• Swift has a smaller community (but it's growing fast). 
• Few developers out there have a lot of experience with the language, so if you run into a problem, getting a solution might not be so easy. 
• Moreover, Swift doesn't offer good interoperability with third-party tools and IDEs. Due to frequent updates, developers often struggle to find the right tools for their tasks. 
• Swift doesn't support earlier iOS versions. You can only use Swift applications for the target iOS7 and later. That's why it's impossible to use Swift for products running on older versions of this operating system.

5. Flutter

Really in 2017 by Google, Flutter took the mobile development scene by storm. In its essence, Flutter is a mobile app SDK together with the framework, widgets, and various tools. The idea was to give developers an easy method for building visually attractive and high-performing mobile applications for both Android and iOS platforms. That's why it's such a popular cross-platform tool in mobile development. 

Popular apps built with Flutter: Four Square, eBay, Google, The New York Times. 

Pros of Flutter

• It's free, open-source, and easy to learn because based on Dart, which also comes with a gentle learning curve. 
• Flutter's architecture is based on reactive programming, which is becoming a modern standard. 
• Thanks to Flutter, developers can write code faster. By using hot reload, they can apply changes to the code and see them straight away in the app. This means that adding features and fixing bugs takes mere seconds. 
• It's a cross-platform technology - developers just need to write one codebase for two apps covering the iOS and Android platforms. 
• Since you're dealing with only one codebase, developers can write automatic tests only once. This also translates into an easier testing process. 
• It comes with its own widgets and designs, which you can also customize. Or create your own.
• Even if users use older versions of the Android and iOS systems, an app written in Flutter will look the same because it supports older devices. 

Cons of Flutter

• Flutter is an incredibly young technology, and its stable release happened only in January 2021. This means developers can expect many changes and improvements that, in turn, could demand changes in the code itself. 
• The fact that Google supports Flutter is meaningful, but it's still very new. Even though it already offers some helpful libraries with functionalities ready to be implemented, they don't cover the entire range of things developers might want. This means that they need to build solutions on their own and that can turn out to be time-consuming. 

6. Java

Java is the most popular programming language of all time. As new languages come and go, the power of Java is only growing. Java in 2020, Java turned 25 years old! Today, it's considered one of the most powerful and efficient languages ever created and widely used in many different areas. 

Popular applications written in Java: Wikipedia Search, Minecraft, Jenkins. 

Pros of Java

• It's just simple. It's easy to learn and understand thanks to a straightforward syntax. 
• The gentle learning curve is made even gentler thanks to the profusion of learning materials and ample documentation. 
• Moreover, Java is far less complex than languages like C++ or C. 
• It's an object-oriented language that helps to boost the flexibility and reusability of the code. 
• It also makes your application more secure because it binds data functions into a single unit that can't be accessed from the outside. Java also doesn't use explicit pointers and thereby reduces other serious security risks. 
• Java applications are cost-effective to develop and maintain since they can be easily executed on any machine. 
• It's platform-independent - Java code can run on any machine, no matter what the operating system is. But only as long as that machine supports the Java Virtual Machine (JVM). 

Cons of Java

• It's slow and might lead to poor performance. 
• There is no denying that Java is memory-consuming and significantly slower than native languages like C++ or C. 
• Developing a complex UI with Java isn't easy. You will find many GUI builders for Java, but creating a complicated UI might be a problem.
• Java code is verbose, which means its sentences are long and complicated – they might be challenging to read and understand.

7. Bonus language: Python

We mention Python as a bonus for two reasons. It snatched the first rank in the Stack Overflow 2020 survey as the most wanted programming language among developers. And today, Python is the most popular language for artificial intelligence and machine learning applications. 

It offers a fantastic library ecosystem with tools that can handle a lot of things like:

• scikit-learn for handling basic machine learning algorithms like clustering, linear and logistic regression, classification, 
• Pandas for high-level data structures, 
• Keras and TensorFlow for deep learning. 

Python uses natural language, so it comes with a very gentle learning curve. It's flexible, platform-independent, and very readable. It offers vast community support, and its popularity is constantly growing. So if you're looking to develop a machine learning application, Python is your best friend. 

Who uses Python in their machine learning applications? Companies like Skyscanner, Robinhood, Venmo. 

WRAP UP

We hope that this list helps you to decide which programming language is a great learning pick for this year. 

Did we miss anything on our list? Or maybe you have questions about any of these technologies? Give us a shoutout in the comments – we're happy to hear your opinion about the best programming languages to learn in 2021.