Programming C without variables is like, well, ... but it often makes sense to have a little bit more structure, and combine data that belongs together in a common collection.

What is abstract data type in C? Abstract data types (often written ADT for short) are data types whose implementation details are hidden from user view for the data structure, but ADTs can be ...

Learn when and how to use different data structures and their algorithms in your own code. This is harder as a student, as the problem assignments you'll work through just won't impart this knowledge.