Shell
- Command interpreter in Unix
- Interprets the first word of a command line as a command name
- Is a user program and not a part of the kernel
- Provides a prompt
- Allows for redirection of input and output
- Provides capability to run jobs in the background
- For most commands, the shell forks and the child execs the
command associated with the name, treating the remaining words on the
command line as parameters to the command
- Allows for three type of commands
- Executable files
- Shellscripts
- Built-in shell commands