An acronym is a word formed from the first letters of a series of words, and you say it as if it's a regular word rather than spelling out each letter. NASA (National Aeronautics and Space Administration) is an acronym: you say “NAH-suh,” not “N-A-S-A.” SCUBA (Self-Contained Underwater Breathing Apparatus) is another: you say “SKOO-buh.”

Acronyms make long names easier to say and remember. Imagine if every time someone mentioned scuba diving, they had to say “self-contained underwater breathing apparatus diving.” That would get tedious fast! Organizations, government agencies, and technical fields love acronyms because they turn complicated names into simple, speakable words.

The key difference between an acronym and other abbreviations is that you pronounce it as a word. FBI isn't an acronym because you say each letter (F-B-I), but UNICEF is an acronym because you say “YOO-nuh-sef.” Some acronyms become so common that people forget they started as abbreviations at all. When you use a laser pointer, you're using Light Amplification by Stimulated Emission of Radiation, but almost nobody knows or cares about that original phrase anymore.

Some acronyms are so useful they become regular dictionary words, like radar (RAdio Detection And Ranging) or sonar (SOund Navigation And Ranging). The lowercase spelling often signals that the word has fully made the transition from specialized acronym to everyday vocabulary.