It's just a word to evoke the idea that serving as much as you can statically while using client-side code and hitting serverless APIs for any needs after that.
The "official website" changed their language from JAMstack (evoking the JavaScript, APIs, and Markup acronym) to Jamstack. It's nothing to be overly concerned about, but I care as someone who has to write the word in a professional context quite often. If we're going to "Jamstack," so be it.
There are all kinds of tech words like this to remember to get right:
- It's Sass, not SASS.
- It's Less, not LESS.
- It's JavaScript, not Javascript.
- It's WordPress, not WordPress. (LOLZ WordPress won't let you spell it wrong. Imagine a lowercase "p".)
- It's webpack, not Webpack.
- It's npm, not NPM.
- It's CodePen, not Codepen.
- It's CSS-Tricks, not CSS Tricks