Linux File Descriptors and Redirection Explained for Beginners

In Linux, a file descriptor is a non-negative integer the operating system assigns to identify an open file or I/O resource. Every process begins with three standard descriptors: stdin (0), stdout (1), and stderr (2). Linux redirection operators allow users to overwrite files with >, append content with >>, and read input from files using <. Error and standard output can be combined using the 2>&1 syntax, while the tee command lets users simultaneously view and save output. The pipe operator (|) chains commands by passing the output of one directly as input to the next.