Programming :: SDL Static Library - Shared Library ?

I'm reading about shared, static, and dynamic libraries. What is SDL? Is it static, shared, or dynamic?

I always thought a library would be a lot of .h and .cpp files compiled separately into .o files and then if you compiled your own program you could use the -l parameter to link the library and it was all compiled together. Now I'm not so sure.

I don't even see any SDL .cpp files in my system anywhere. All I have are lots of SDL .h files in /usr/include/SDL and I don't really understand the code in them.

I'm making a wild guess here: SDL is a shared library. SDL itself is NOT compiled into my program, therefore SDL must be on any system my program tries to run on. When I compile and link SDL all it needs is the header files to know what SDL function and objects it can use. And then on every system it uses an already compiled SDL shared library thingy somewhere.

So... where is that part of SDL? All I can find are header files.

I'm thinking the advantage of shared libraries is that someone could say update SDL on their own system and take advantage of the new features without having to download new executables with the new version of SDL compiled into them for every program that uses SDL.

So if I'm making an editor and a game engine and they both use a lot of the same .cpp and .h files that I wrote and I'm tired of updating one and then the other and I need to turn them into a library, then a shared library might be kind of a silly solution. I could just make a static library. Right? Because it's not SDL. Nobody else is ever going to use this library.