The glibc 2 HOWTO covers installing and using the GNU C Library version 2 (libc 6) on Linux systems.
This manual is available in the following formats:
Any Unix-like operating system needs a C library: the library which defines the ``system calls'' and other basic facilities such as open, malloc, printf, exit...
The GNU C library is used as the C library in the GNU system and most systems with the Linux kernel.