PATH determines what binaries are known, colon delimited defining the order of looking for commands

Shims are executables that can intercept commands and change arguments, handle the operation, or redirect the operation


Tool for transferring data from or onto a server, can use almost all protocols


Netcat is a computer networking utility for reading and writing to network connections using TCP or UDP


For logging into remote machines. ssh hostname


Manual pages for any command line tool. man some-command pulls up help info about a command.

touch a b c

Creates or updates last write date of files a, b and c.


Echo is a print cmd to standard output. Takes arguments and prints them delimited by spaces. alternatively, can take a literal string using quotes.

$ echo Some      Test
Some Test
$ echo "Some      Test"
Some      Test


Evaluates the file (could be a shell script for example) following the command, as a list of commands, executed in current context.


builtin commands are contained within the shell itself. Does not invoke another program.


For finding files. Allows user to execute other commands on them. In the following cmd, pattern describes a glob pattern for finding files:

find . -name "pattern" -print