When religious wars ignite over computer languages (starting with questions like “which is the best” and quickly degenerating into “which is one only a heathen would program in”…), or when someone wants to promote a language’s increase, you’ll often hear about the Tiobe Index, an index based on search engine queries on programming topics (you can see the latest results here).

Although I have some reservations about the index (it after all refers to search engine queries, so for example a poorly documented/hard to understand language could have a larger proportion of searches online than a simple to use/easy to write one), it is a useful tool as to how languages ebb and flow in popularity.

Here though is the point of this article: C is the Gateway Language.

Based on May 2014’s info, if you learn C (16.9%) and then learn ‘C with classes’, you’re good to go with C++ (or 22.9% combined of the Tiobe index). But C++ gets you much of which you need to know to program Objective-C, so with a bit more mental effort, you’re up to 34.7%

And from there? Once you know C++ you also are close to understanding Java. And of course, knowing Java gets you going on Microsoft’s Java ‘clone’, C#. And finally, once you’ve figured out the C# environment, you are well on the way to change the syntax a bit, and do Visual BASIC .NET work. Or move to the C-like Javascript. Or the similar PHP. Or even take a stab at Python.

End results? Starting with C, and a desire to add just a smidgen extra knowledge each time, you’re well on your way to understanding some of the most important computer languages in use, with over 55% of the online search activity, as this chart totals up from the May 2014 Index:

C. Over forty years old, and arguably still the most important computer language there is to learn.