Source code

Definition source code

Programs and websites use it as a basis – but what exactly is source code?
Source code is the human-readable text of a computer program or a website.
You can think of it as a software document written in a programming language. It serves as the basis of any computer program, because the exact rules and specifications of all the functions that the program should perform are defined here.

However, in order for the computer to understand the instructions, the source code must be translated from the human-readable programming language in which it was written into machine language. This is done by compilers or interpreters, depending on the programming language used. After compilation, the computer can read the instructions from the source code and implements them in the form of a program.

What does the source code look like?

What a source code looks like depends on which programming language was used. Because this defines the conventions, i.e. the syntax and terms – comparable to a foreign language, which has its own grammar.

Depending on how comprehensive the program is, the source code can quickly become very large. With large programs with a multiplicity of functions it consists also quite times of several documents. Also graphic representations of program parts are possible.

In addition to programs, Internet pages also have a source code as a basis. This is written in the HTML markup language and significantly determines how the page looks in the browser. In addition to the HTML structure, the source code of the website often contains elements written in programming language. Java Script, for example, is often used.

How to create a source code?

Even before you want to create a source code, you need to clarify some important questions:

• Which programming language do you want to use?
• Can you implement all functions for your program with it?

Depending on which programming language you ultimately choose, you will need a specific development environment. To write a source code for a website, HTML, CSS and JavaScript are usually used. A simple text editor is sufficient for this.

In order for the source code to work properly, you need to make sure that all the standards of the programming language are met. These differ, depending on which one you have chosen. If there are errors in the source code, the computer will not understand the instructions and will not be able to implement them.

How to view the source code of a page?

When you visit a website, you don’t see any of its source code at first. Instead, the browser displays the fully rendered page. In this view, the computer has already implemented all the instructions defined in the source code. However, you can display the HTML code in any browser. For example, you can read metadata that you don’t see on the rendered web page.

If you want to display the source code on a website, there is usually a simple key combination for this in common web browsers:

• Google Chrome: Right click, then “Show source”.
• Firefox: CTRL + U / right click, then “Show page source”.
• Safari: CMD + ALT + U

For programs, the source code is not always visible to protect your own data. In some cases, it is protected by copyright or encrypted, so that you must first acquire usage rights through a license. Especially with complex applications, the source code is very extensive and does not necessarily have to be in one file, but can also be divided into several.

Source code and SEO

Search engine bots do not see web pages in the same way as a human who calls them up – they merely read the source code. Accordingly, it is important that the source code is error-free and well-structured, because this can affect the ranking. A well-structured source code brings a clear advantage here.

You should reduce the source code to the most necessary structures, otherwise it may not be read completely. A lean source code also improves loading times and makes it easier for the crawling bots of the web browsers to read out information. This is because in the source code, in addition to the execution instructions to the computer, you will find other information such as metadata, which is useful for search engine optimization. Information about the page’s links (e.g. whether they are DoFollow or NoFollow links) is also stored in the source code.