What Is Scala?

Scala, or Scalable Language, is a general-purpose programming language that supports object-oriented programming and functional programming styles.

Written by Artturi Jalli
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UPDATED BY
Abel Rodriguez | Aug 19, 2025
Summary: Scala is a statically typed programming language that combines object-oriented and functional programming. It runs on the Java Virtual Machine, supports Java libraries and is used for data processing, distributed computing and web development. Scala emphasizes concise, typesafe and immutable code.

Scala is heavily influenced by the Java programming language so  these two are very similar. As a matter of fact, you can code Scala using some Java libraries.

What Is Scala Used For?

  • Data processing
  • Distributed computing
  • Web development

 

How Does Scala Work?

In Scala, every value is an object by nature because the classes and traits give behavior to the objects. This is what makes Scala an object-oriented language. You can extend Scala classes with subclassing and use a mixin-based composition instead of multiple inheritance.

Scala is also a functional language that supports creating memory-efficient anonymous and higher-order functions. What’s more, you can nest the anonymous functions and curry them.

Finally, Scala is a statically typed language but you don’t need to specify the type information. This is distinct from other statically typed languages like C. In C,  you must define the types of the objects upon creation.

Scala Tutorial Full Course. | Video: Telusko

 

Why Learn Scala?

Scala is not a top 10 popular programming language but it’s still worth learning. Not only are Scala developers in high demand, but developers can use Scala to build scalable applications for data processing, distributed computing and web development.

This is all possible because Scala is a unique combination of functional and object-oriented programming paradigms. Static typing helps prevent bugs in complicated programs because static typing expresses programming patterns in an understandable way. 

Scala language runs using the JVM (Java virtual machine) runtime, which makes it a high-performance language. You can also access versatile Java libraries using Scala.

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Scala vs. Java

With Scala, you can write clearer and more concise code using the type inference, function passing and other features to make the code less verbose. These features don’t exist in Java.

Scala’s design makes it easy to express programming patterns in a typesafe and concise way. Scala encourages an immutable coding style, which supports safer concurrency.

Scala supports lazy evaluation, which means variables don’t require computation before someone calls them, which saves memory. In Java, there are no lazy evaluation options.

Scala also supports operator overloading, which means you can give a new meaning to any operator. You can also create completely new custom operators, which isn’t possible in Java.

Scala is sometimes harder to understand than Java because the code uses nested structures (functions inside functions). Although nesting code can make it more clear, doing it badly does the opposite. This problem doesn’t exist in Java.

Scala has experienced some compatibility challenges between versions, unlike Java, which emphasizes backward compatibility. This means the code works in older and newer Java versions without issues.

Last but not least, Scala is a bit more difficult to learn. This is because Scala’s syntax is a bit trickier and there is less code to write in Scala. Less code means more abstraction. For example, the lack of type information in the code means the code reader must determine the type information based on the context.

Frequently Asked Questions

Scala is commonly used for data processing, distributed computing, and web development.

Scala treats every value as an object and uses classes and traits for behavior. It also supports higher-order and anonymous functions, function nesting, currying, and immutability.

Yes, Scala is statically typed, but it features type inference, so developers often don’t need to explicitly declare types.

Scala allows for more concise code through type inference and functional features. It supports operator overloading, lazy evaluation, and encourages immutability. Java emphasizes verbosity and backward compatibility.

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