popd

popd is a shell builtin command used in conjunction with a directory stack. It removes the top directory from the stack and changes the current working directory to the new top entry. In practice, it lets users return to a previous location after using pushd to move to another directory. The directory stack is a list maintained by the shell; pushd adds a directory to the stack and switches to it, while popd removes the top entry and switches back.

The command is commonly available in Bash, Zsh, Ksh, Tcsh, and other shells that implement a directory stack. It is not part of the POSIX sh standard. The current contents of the stack can be viewed with the dirs command, and in Bash the stack is also accessible via the DIRSTACK variable.

Usage notes vary by shell. Without options, popd typically pops the top entry and changes the current directory to the new top. Some shells support options or numeric arguments that modify which entry is removed or suppress directory changes, allowing more granular manipulation of the stack. In daily use, popd is often paired with pushd: you can push a new directory onto the stack, work there, and then popd to return to your previous location. For quick reference, many environments also support cd - to return to the previous directory, independent of the directory stack.

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