Where does the API reside?
The bulk of the API functions are encapsulated in a set of DLLs -
kernel32.dll
user32.dll
gdi32.dll
shell32.dll, etc.
These DLLs form the core of the Windows OS and are present on all windows
machines (At least the ones that are bootable :)). So unlike when you access
a function from a third-party DLL, you don’t have to ship anything with your
product when you use an API function. The effect this has on the distribution
size and speed of your application has to be seen to be believed.
Note: In addition to the DLLs mentioned above certain other
DLLS also find place in an API Programmers notebook. These are used to provide
certain special functions like Encryption, Security related features etc. We
will discuss some of them in later articles of this series.