Is there a way to list all the files under a directory and it's subdirectories that were changed or modified within a time period?

For example I want to list all the files under the /home directory and it's subdirectories that have been created or modified within the last system boot or within the last 30 days.

Thanks!

# The 'ls' family (this assumes you use the GNU ls)
alias la='ls -Al' # show hidden files
alias ls='ls -hF --color' # add colors for filetype recognition
alias lx='ls -lXB' # sort by extension
alias lk='ls -lSr' # sort by size
alias lc='ls -lcr' # sort by change time
alias lu='ls -lur' # sort by access time
alias lr='ls -lR' # recursive ls
alias lt='ls -ltr' # sort by date
alias lm='ls -al |more' # pipe through 'more'
alias tree='tree -Csu' # nice alternative to 'ls'

Here are some nice aliases from the Avd-Bash-Scripting-Guide.
If you don't understand 'alias' and your environment just:

ls -lcr

Also you should use man. e.g. "man ls"