mtime — modified time = last time file contents was modified
ctime — changed time = last time file inode was modified
Numeric arguments can be specified as:
+n for greater than n,
-n for less than n,
n for exactly n.
Note that “less than” means “strictly less than”, so -mtime -14 means “last modified at the current time of day, 13 days ago or less” and -mtime +14 means “last modified at the current time of day, 15 days ago or more”.
