The BITS Group feels that the following represent, at a minimum, your responsibility. Many of us maintain files that are not necessary. Such files are usually temporary files generated as a result of programming language compilations, mail, etc. It will stay in the MAIL file until you manually delete it. This is something that you will have to do manually.
Typical examples are programs that do simulations and mathematically intense solutions.
There are many suggestions for password composition. Some would say that placing a one or more number in your password makes it harder to remember. Numbers in passwords make them exponentially harder to guess. The BITS Group recommends that you use two unrelated words separated by one or more numbers. For example, T1ME4fun might be easy to remember.