too long; didn't read linux from scratch
< installing an init — installing a shell — installing a bootloader >
A shell provides a means for users to interface and execute tools on the machine. They are a tool that allows the user to be in direct control of the system. Shells also give users the ability to script, and to some degree, automate specific tasks or create routines that can be executed.
While most shells have the same basic functionality--that is, calling binaries and passing arguments to them--there are additional features that they provide. In some you will find rich text completion for commands, in others you may find that in lieu of functionality they prioritize speed.
Installation guides
tl;dr lfs needs help! feel free to contribute if you find something missing