Multiple Threads and Multiple Source FilesPreprocessor Directives
Templates
Enumerations
All of them, and regularly.
There are many more similar things though. In order to be a good programmer, it's really important that you know what all of them are. If you don't, how are you going to know to use them when applicable?
Some questions for you:
Do you use an OOP or procedural structure to your code? And I don't just mean inheritance, but absolutely everything from interfaces, access control, abstraction, virtual, design patterns, etc.?
What about LINQ in C#, VB, ...?
events and delegates?
static, volatile, readonly?
unsafe, fixed
lock?
yield?
asm?
smart pointers? (..ish)
new/delete, malloc,calloc,etc./free,
That's off the top of my head, there's probably loads of others too. I was thinking about C based languages when writing this, but I am sure most translate across in one way or another to various other languages. And yes, I do use most of these frequently (not unsafe, fixed, or asm very much though)
Richard