There are many built-in functions in E.
We've already seen a lot of string and list functions, and we've used
WriteF for printing.
The remaining functions are, generally, simplifications of complex Amiga system functions, or E versions of support functions found in languages like C and Pascal.
To understand the graphics and Intuition support functions completely you really need to get something like the Rom Kernel Reference Manual (Libraries). However, if you don't want to do anything too complicated you should be able to get by.
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