Terms and Abbreviations in Engineering, Technology, & Science

Last updated: 23 March 2024

This is an extensive glossary of terms that electrical and computer engineers use: acronyms, abbreviations, words or phrases, names, numbers.

Entries are in alphabetical order, numbers before letters, discounting spaces and punctuation. In the navigation bar at left, click the first letter of the term you’re looking for, or # if the term is or begins with a number. If unable to find a phrase, look for its acronym. Related terms are cross-linked for quicker browsing.

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Why?

As a neophyte electrical engineer in the early 1990s, I observed that tech writers took a perverse joy in using cryptic acronyms. Many still do, but at the time the convention of expanding an acronym at its first use in a document had not taken hold. On the rare occasions when they spelled things out, I jotted down the expansions as a sort of professional crib sheet. I kept them in strict alphabetical order, because how else would you do it?

Mere acronym expansions weren’t enough, so I began appending short explanations of what the terms meant and how they were used. Then I broadened the list beyond acronyms. Then I added a few simple bitmap diagrams... and, as the years went by, my crib sheet snowballed into a book-length electronic document.

It became so unwieldy that at last I tried to embed hyperlink navigation. The document file format proved ill-suited to this approach. So, instead, I broke the file into twenty-seven sections – one for each letter of the English alphabet, and one for the relatively few numerical terms – and converted them to hand-coded HTML, with a unifying navigation bar.

The resulting Web site’s origin as a collection of notes for myself means that many of the explanations assume knowledge of computers or engineering, especially digital communications. There are more accessible entries for subjects I was just learning about, or from when I was in a pedantic mood and thinking of a general audience. The latter happens more as I get older, which is probably a bad sign.

Some entries are out of date, even to the extent of describing, in the present tense, technologies long since gone to their eternal rest. I mostly leave these descriptions of dead tech in place, fossil footprints for paleotechnologists to study. It might take me years to add an update or RIP where one is called for.

See, that’s how it started.

The growth of the Web, with its many crowdsourced references led by the ever-remarkable Wikipedia, has eclipsed my humble one-man list. I continue to update it because doing so makes me a better engineer. I maintain it online partly as an exercise, partly in the hope that others will find it useful, and partly for an excuse to have my own domain with whatever geek cred that brings me.

I prize explanations that are clear, concise, relevant, impartial, and, above all, accurate. Where I trespass against these values here, it’s probably unintentional, but the fault is mine alone.

— ee, January 2013

This site uses HTML5. It uses JavaScript to permit styling of certain HTML5 elements in older browsers, and for animation on select pages. It employs no pop-ups, user tracking, fingerprinting, client-side storage, third-party cookies, or interactive content, because the author has no use for that stuff and doesn’t know how to do half of it.