Boats, Trains, and Automobiles. And Computers.

Why Do We Have Log Files?

Boats.

Back in the 1600s, when sailors needed to measure the speed of a ship, they would tie a rope to a log and lower it off the stern. The rope had knots spaced out at regular intervals. After the log had drifted out behind the ship for a certain period of time, they would count the number of knots between the ship and the log. This was used to compute their speed in knots. A knot is one nautical mile per hour.

The book where these nautical calculations and other events and observations were recorded became known as the logbook or the "log". The act of recording this information into the logbook also became the verb "to log".

This terminology was borrowed for computing. A file were events are logged became known as a log file or just a log.

Why Do We Have UTC?

Trains.

Historically, cities would set clocks so that "noon" would match whenever the sun was at its peak in their particular region. Cities separated by a few hundred miles could have times separated by several minutes. This was fine until trains started to connect distant locations in the mid-1800s. In order for schedules to work, railways needed to adopt a standard time. They chose Greenwich Mean Time (GMT), which was set by the Royal Observatory in Greenwich, London.

GMT was succeeded by Coordinated Universal Time (UTC) in the mid-1900s. UTC is managed by several atomic clocks at the US Naval Observatory in Washington, DC. International standards for exchanging time data are anchored on UTC. And it's the default time zone for the storage of time values in databases.

The time zone that was the standard for train networks became the standard for computer networks.

Why Do We Have Throttling?

Automobiles.

"Throttle"—possibly derived from the word "throat"—means to choke or strangle. For a combustion engine, throttling means to regulate or reduce the power of the engine by choking off its supply of fuel or air.

Carried forward into the realm of computing, throttling means to limit or reduce the speed of something. We might throttle a certain process or activity so that it doesn't consume an unfair share of system resources.