You’ve dropped inside a directory with dozens of sub-directories. You know there’s a file inside this directory that you need, but you aren’t sure where it is. find can help!
meanii ✓ find . -name CS101
The ‘find’ command lets you walk a file hierarchy (the first argument to the find command), and search it on several different dimensions. You can type man find into your terminal to see them all, but the example above uses the -name flag to search for filenames including the character sequence CS101. Instead of bumbling through directory after directory like someone searching for an orphaned sock under the bed, consider using find.