Filter finding files by creation date

Find files that were created within the past 7 days

$ find /path/to/dir/ -mtime -7
./file_from_yesterday
./file_from_three_days_ago

Find files that were created until 7 days ago

$ find /path/to/dir/ -mtime +7
./file_from_ten_days_ago
./file_from_thirty_days_ago