Log
Log
Data automatically recorded to capture what a computer or program was doing while running.
In Simple Terms
A log is like an activity diary for a computer or program — it's data that automatically records what happened and when. It captures information in chronological order, such as who accessed a website or whether any errors occurred in a program. When something goes wrong, you can trace back through the log to pinpoint the cause. Beyond troubleshooting, logs are widely used to track how a system is being used overall.
Behind the Name
The word 'log' traces back to an actual piece of wood. Sailors once threw a wooden log overboard on a rope to measure a ship's speed, then recorded the readings in what became known as a logbook. Over time, keeping that written record came to be called 'logging,' and the term carried over into computing to describe the automatic record a system keeps of its own activity.
Take a Closer Look!
A log is a chronological record of what a computer or software has done and what actions a user has taken, stored for later review.
It is automatically written to a file or database so that the system's activity history can be checked at any time.
In programming and infrastructure, logs are essential for understanding the state of a system.
A server log, for example, records detailed information such as who accessed which file and when.
Other common types include error logs, which capture information about errors that occurred during a program's execution.
Reviewing logs on a regular basis helps you catch system issues before they escalate and monitor for unauthorized access.
In large systems, the volume of recorded log data can be enormous — but analyzing it also provides valuable insights for improving the service.
To put it simply, logs are a vital piece of evidence that makes the invisible workings of a system visible.