Source code is the command text behind any software. It defines the rules for how the program behaves in a particular programming language. It is important for the source code to be error-free. Otherwise, it can lead to parts of the software malfunctioning or the whole program crashing and even damaging hardware.
There are a number of popular programming languages. Which one is used depends on what the purpose of the software is:
In order for a computer to correctly execute the source code, it has to be translated. This happens with the use of an additional program: a compiler or an interpreter. An interpreter directly executes the translated source code. However, this requires a lot of memory and slows down the execution. A compiler collects the translated source code into an executable file.
While a markup language does not result in a program, it can contain a program. Rather, markup languages are used to structure content. They are most commonly used for websites. The most widespread markup language is HTML. Another popular one is XML.
Similar to other forms of intellectual property source code is protected by copyright law. This means that distributing the source code of the source code of a program or homepage without a licensor’s consent is illegal.
In contrast to this, the open source scene actively advocates collaboration on and free distribution of source codes. The aim is to collectively improve software and programming practices in the long run.