binutils, gcc and glibc are the three important parts of the GNU tool chain.
binutils is a series of binary tools, the two most important tools are: as (assembler) and ld (linker). as converts the assembly code generated by gcc into binary code, and ld converts multiple object file codes into a library file or an executable program. In addition to as and ld, binutils also includes tools such as ar, nm, objcopy, objdump, and readelf.
gcc is a compiler suite in the tool chain. It currently supports not only C language, but also C++, Java, Fortran, Objective-C and Ada. At the same time, gcc also supports many architectures.
glibc implements the traditional POSIX API interface, which communicates with the kernel through system calls and provides more advanced services for user-mode programs. With it, you can easily develop user-mode programs.
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