what's different between lib and lib-devel in yum?

I'm compiling a software that depends on libpcap,so I yum install libpcap,but when I ./configure it still reports can't find libpcap开发者_如何学运维,so I run yum install libpcap-devel and this time it works.

My question is,what's the difference and what exactly was ./configure looking for when it says libpcap not found?

"lib" contains the things your program needs to run (the ".so" file). "lib-devel" contains the things your program needs to compile (the header files).