Kops Make Great Theft Prevention Experts is a mnemonic for prefixes from SI units. The theme of this mnemonic is NetHack.

An SI unit, such as a metre, gram, litre, or newton, can have a prefix attached to represent a power of ten, such as 1,000. For example, a kilometre (km) is 1,000 metres, a megagram (Mg) is 1,000,000 grams, a gigalitre (GL) is 1,000,000,000 litres. This has applications in computing also: a kilobyte is varingly 1,000 or 1,024 bytes. (The number 1,024 is 2 to the 10th power; a megabyte would have 2 to the 20th power bytes.)

The mnemonic Kops Make Great Theft Prevention Experts is to memorise the order of of prefixes for every third power of ten from 3 to 18:

kilo- Mega- Giga- Tera- Peta- Exa-
103 106 109 1012 1015 1018

The abbreviated prefix (for example, km for kilometer, MB for megabyte) is always uppercase, except that k for kilo- is lowercase. The mnemonic does not help here; Kops is the only proper noun.

The mnemonic is also flawed. During actual gameplay, Keystone Kops do not appear until after you rob a shop. Thus they do not actually prevent the theft, they react to it! The shopkeeper, by blocking the door, is actually the best theft prevention expert.

Community content is available under CC-BY-SA unless otherwise noted.