pushd, popd, and dirs commands

If you spend a lot of time in the command line, you will have to cd to different directories frequently.  Instead of the cd you can use pushd command to switch to a different directory.  pushd command pushes the new directory into a "directory stack".  Later you can return to your original location using popd command.  Both pushd and popd print the latest contents of the directory stack.  You can also use dirs command see the directory stack.  Items in the directory stack are indexed from 0.  You can reference any directory in the stack by typing ~ followed by the index.  A sample session using the directory stack (user input is in bold font):

~% pushd /tmp
/tmp ~
/tmp% pushd /etc
/etc /tmp ~
/etc% pushd /var
/var /etc /tmp ~
/var% dirs
/var /etc /tmp ~
/var% popd
/etc /tmp ~
/etc% pwd
/etc
/etc% dirs
/etc /tmp ~
/etc% cd ~1
pingala /tmp % dirs
/tmp /etc ~

As the directory stack becomes larger, finding the index of a directory in the stack becomes harder.  I use -v flag to print the numeric index along with each item:

/tmp% dirs -v
0       /tmp
1       /etc
2       ~

If you are like me, you wouldn't remember to use pushd.  For users like us, the zsh has an auto_pushd option.  When it's set, all cd commands are treated like pushd commands.  With that option enabled, I use the shell normally, but zsh remembers the directories I have recently been to.  I can use dirs -v any time to get a list of recent directories and use the ~ notation to return to one those directories.