18.104.22.168. Source packages
The largest part of Linux programs is Free/Open Source, so source packages are available for these programs. Source files are needed for compiling your own program version. Sources for a program can be downloaded from its web site, often as a compressed tarball (program-version.tar.gz or similar). For RPM-based distributions, the source is often provided in the program-version.src.rpm . Debian, and most distributions based on it, provide themselves the adapted source which can be obtained using apt-get source .
Specific requirements, dependencies and installation instructions are provided in the README file. You will probably need a C compiler, gcc . This GNU C compiler is included in most Linux systems and is ported to many other platforms.