A .log file is a simple text document that records events generated by software, operating systems, or servers. It automatically tracks chronological entries (timestamps, actions, messages, errors) related to the operation of a program or system. Unlike formatted documents or databases, log files are primarily sequential text records. They are typically found in specific directories on computers or servers, often with names ending in ".log" or ".txt".

These files serve as vital histories. For instance, the Windows operating system logs system errors, warnings, and information events in files accessible via Event Viewer. Web server applications like Apache or Nginx generate access and error logs, listing every website visitor request and potential problems encountered. System administrators, developers (especially for debugging), and IT support teams heavily rely on these logs across industries like IT operations, software development, and web hosting to diagnose crashes, monitor security, or understand user activity.

Deleting .log files is generally safe if done judiciously. They can consume significant disk space over time, making deletion beneficial for freeing up storage. However, crucial limitations exist: deleting active logs (while software is running) might cause errors, and removing logs prematurely eliminates valuable troubleshooting data needed to diagnose recent problems. Ethically, log retention policies are often mandated for security audits or compliance in sectors like finance or healthcare. Automated log rotation tools are preferred for deletion as they manage retention reliably without data loss.