Renaming files by date created or modified means changing a file's name based on timestamps stored in its metadata. Creation date reflects when the file was first saved, while modification date shows when its content was last changed. Unlike simply typing a new name, this process typically requires specialized tools because standard filename editing doesn't automatically access or incorporate this metadata directly.

A common practical example is organizing personal photos; you might rename vacation pictures as "2024-07-15_Beach.jpg" using their creation date for chronological sorting. In business settings, version control for documents like reports can be streamlined by renaming files to "ProjectPlan_Modified_2024-07-15.pdf" after each update, instantly showing the latest version. This is frequently done using built-in tools like macOS Automator or Windows PowerShell scripts, or third-party bulk renaming utilities available on all major desktop platforms.

Automatically incorporating timestamps offers significant advantages for organization and retrieval in large collections, reducing manual effort. However, limitations exist: creation dates may not reflect the actual content origin if files are copied (resetting the date), metadata can sometimes be inaccurate or missing, and exact tools/commands differ across operating systems. Users should also be aware that modifying dates purely for organizational reasons doesn't inherently present ethical issues, but altering timestamps to misrepresent file history could raise concerns about data integrity and provenance.