As a developer, you probably have had to use multiple languages in the various projects you work on. With over 600 notable programming languages worldwide and technology changing so rapidly, it can get confusing on which programming languages are trending up or down. In the spirit of continuous learning, here are a list of top 5 programming languages for 2021 that would benefit you well to have in your toolkit to ensure you stay marketable.

The top 5 languages to know for 2021 are:

  • Python
  • Javascript
  • Golang (GO)
  • Kotlin
  • Java

Python

It is no surprise that Python leads this list as it's becoming more and more popular year after year. It's often recommended as the first programming language to learn if you are new to programming because of its simple and flexible syntax. You can also quickly build something usable which motivates you to keep learning. Python is ranked #1 on Stack Overflow's Most Loved, Dreaded, and Wanted list, meaning that developers who do not currently use it say that Python is the #1 language they want to learn.

Python is not just for "new programmers" though, as the top tech companies Google, IBM, NASA, and Reddit are just a few of the tech giants that use Python for a wide range of use cases. Python is used for a multiple of use cases such as building web applications, pentesting, DevOps automation, or even big data.

Any good programming language will have a plethora of library support, tutorials, and a strong community. If you start to learn Python, you will find numerous avenues of help from the larger developer community.

JavaScript

Pretty much the entire web is built on HTML, CSS, and JavaScript, not to be confused with Java which is a completely different language. If you want to get into any kind of web development, you must learn JavaScript. JavaScript greatly enhances a website's experience as it makes it more interactive versus a normal static page with straight HTML. Want a popup to be shown when a button is clicked? You can use JavaScript to do that.

JavaScript is dynamically typed language which means that the variable types are determined at run time versus compile time. This can allow for more flexible and concise development, albeit at the cost at strong error checking before a program runs.

There is a mature ecosystem of frameworks due to the large community support of JavaScript. You may have heard of such frameworks as React or Angular or the JavaScript engine Node which allow you to create complex web applications.

With the wealth of jobs on the market requiring JavaScript, a strong community support of the language, and it's ability to enhance your web applications, JavaScript is a noteworthy language to learn in 2021.

GO

GoLang (GO) is a relatively new language that was introduced in 2009 by Google. The goal was to construct a language that had a great balance between performance and easy of use. As Go is a compiled language, it's performance is similar to C/C++ while it also provides high level features that are common in interpreted languages such as garbage collection. Now that Moore's Law is fading, it's becoming more and more important to write fast and efficient code. While you can write multi-threaded programs in languages such as Java, they just aren't very efficient at doing. For instance, each thread in Java takes up about 1 MB in the heap which starts to hit hard once you have thousands of threads open. Golang was built for concurrent execution with goroutines which are much faster and use a smaller memory footprint.

Kotlin

If you intend to do Android development, Kotlin is the way to go. Introduced by JetBrains in 2011, Kotlin is now officially adopted as an Android language since Google IO 2017 and the adoption has skyrocketed since. Some of the benefits of Kotlin over Java for Android development are speed of development and safety. Kotlin was built so you could develop quickly and concisely without having to go through the typical ceremony of code that you do with Java. Additionally, Java handles nulls poorly which has come to be known as The Billion Dollar Mistake with so many Android applications having crashes due to null pointer exceptions.

Additionally, one of the nicest features of Kotlin is it is 100% interoperability with Java. This means you don't have to spend tons of money and time porting your existing Java applications over to Kotlin as you can do it incrementally.

Kotlin is definitely the way of the future for Android development so would be a great language to learn and use in 2021.

Java

Despite the above section praising Kotlin over Java for Android development, Java is still the most popular language in the world for development.  You'll find Java being used virtually everywhere, from web to non-web, operating systems, IoT devices and many more. Thus, the job market will always have a need for Java developers in the near future making it a great skill to market yourself with.

Java is a very mature language and often recognized as a good "first programming language" to learn as it teaches you how to think like a programmer with many concepts such as Object Orientated Programming. Having Java as a core language will better enable you to learn more languages as you learn to think like a programmer. Being a mature language, Java has one of the most rich and full communities and library support. You'll find a breadth of material to support you in your journey to be a Java developer, making this a great language to learn in 2021.