Understanding a guitar's "Action"

"Action" on a guitar is the amount of space between the strings on a guitar and the fretboard. Having high action means it's harder to put one's fingers on a chord because there is too much space between the string and the fretboard. The more space, the harder one has to work. Having low action means it is easier to put the fingers on the chords, and play guitar. Low action is good up to a point. If one lowers it too far, the strings buzz too much because they are too close to the frets. Thus, fret buzz.

Acoustic guitars usually have higher action than electric guitars. The reason this is so is because acoustic guitars are usually used as rhythmic instruments, for accompaniment. This is not always the case, for sure, but it is so most of the time. If there is more force, like in the case of strumming a chord strongly, the strings need more room to vibrate fully. The more room means the more area for the string to travel without fret buzz. The less room, and the more chance for fret buzz. This could be a problem unless you play Slayer songs and want to get beaten up by Kerry King.

There are also a couple of reasons why electric guitars have lower action. One is that they have a very small acoustic value; Most are solid-body and can't project loudly. They must be plugged in. An amp naturally covers a bunch of fret buzz by distortion, or, um, drunkedness. The second is that electric guitars are made for playing leads.

Choosing a guitar often has to do with the action. I want low action usually, even on an acoustic. If you are starting from scratch, the acoustic guitar is a good way to start. If you can get past the higher action of it, and if you can deal with about two weeks of callous forming on your hand, then you'll be just fine if you switch to electric.