The difference between #include and #import is that
- #include allow you to include the same file many times.
- #import ensures that the preprocessor only includes a file once.
C programmers tend to use #include.
Objective-C programmers tend to user #import.
* Compiling a file in Objective-C is done in two passes. First, the preprocessor runs through the file. The output from the preprocessor goes into the real compiler.
Preprocessor directives start with #. The three most popular are