For many different programming languages, a function can be important and can therefore be a key concept to learn when someone is interested in software and computer programming. A function can also be termed as a subroutine, procedure, or sub-query. How is a function important? For instance, if a company or institution has a library of many different programs, these programs can therefore consist of millions upon millions of lines of a source code. In the interests of time and space, you would like to keep from duplicating a certain source code in many different places.
Why is duplication so undesirable? If a source code is duplicated in many different places, it is being needlessly copied, and it can spell Hell for the programmer and troubleshooter when things go wrong down the line. If the source code is actually erroneous, the programmer or troubleshooter will have to correct the code in all the different places that it appears. If the source code has to be updated or improved in order to make the program either run faster or perform more operations, then the source code has to be modified, improved, and updated in all the places that it appears. And if the source code has to be removed and replaced with a new source code, then it has to be erased and replaced with the new code in every single place that it appears.
This is indeed time-consuming, and it can lead to more errors because of all the human intervention that has to be done. On the other hand, if there are functions that are built to handle all the different programs, then only one or a few changes need to be made should there be errors, or should the source code have to be updated, modified, improved, or changed. You can think of the function as an umbrella: it covers all of many different programs beneath it, so that you do not have to cover each program individually.
Having a single source code serving as the function is also advantageous when you have to introduce a new program that still makes use of that same source code. Because the source code is already available as an overall function or sub-program, you do not need to add the source code to the new program. You only need to find a way for the new program to interact with the source code itself.
These are only a few facts that you need to know about functions in computer programming. For more information, read up on the latest computer programs, how different programs can interact with each other using some umbrella or overall scripts, and how different programs can be improved when using functions.