What is pushd (Push Directory) in Bash?

With no arguments

pushd 

With no arguments, exchanges the top two directories and returns 0, unless the directory stack is empty.

First Form

pushd [-n] [dir]

if supplied, have the following meanings:

• -n: Rotates the stack so that the nth directory (counting from the right of the list shown by dirs, starting with zero) is at the top.
• or ?? -n Suppresses the normal change of directory when adding directories to the stack, so that only the stack is manipulated.
• dir Adds dir to the directory stack at the top, making it the new current working directory.

pushd returns 0 unless the cd to dir fails.

Second Form

pushd [-n] [+n] [-n]

where:

• +n: Rotates the stack so that the nth directory (counting from the left of the list shown by dirs, starting with zero) is at the top.
• -n: Rotates the stack so that the nth directory (counting from the right of the list shown by dirs, starting with zero) is at the top.
• -n Suppresses the normal change of directory when adding directories to the stack, so that only the stack is manipulated.

pushd returns 0 unless the directory stack is empty, a non-existent directory stack element is specified, or the directory change to the specified new current directory fails.

Go away and returns

# we are now in /
pushd /aDir/
# we are now in /aDir/
popd
# we are now back in the starting current directory /