Pipe allows the output of one command to be used as input for another command. The "|" symbol is used to connect commands. Common examples include using "ls | more" to view a directory listing page by page or "who > userlist.txt" to redirect the output of the who command to a file. Linux treats the keyboard, terminal screen, and error messages as standard input, output, and error. Redirectors like "<" and ">" can change where input and output are directed. Commands like sort, grep, and more are examples of filters that take input, manipulate it, and produce output.