I suggest beginning guitarists learn to play on an electric guitar because electric guitars are easier to play, and in the beginning, you need all the help you can get! I make an exception for a person who loves acoustic guitar and only wants to play acoustic guitar music. Remember, you can always play acoustic guitar after first learning on an electric guitar.
Some people tell me they want to learn on an acoustic guitar specifically because acoustic guitars are harder to play, but the guitar is already hard to play. Do you really want more discouraging challenges that take extra time to overcome, or do you want to have fun playing your favorite songs and building solid transferable skills? Think of learning to drive a vehicle with a manual transmission. It’s harder to learn on a truck and trailer than on small car. You still learn how to shift gears, it’s just physically easier on the small car, so you learn faster.
Electric guitars are easier to play because they usually are strung with lighter strings, and the action (the distance from the string to the fretboard) is usually lower on electric guitars. The skills you learn are the same, you are just less likely to quit or injure yourself because it takes longer to get clear notes and chords out of a big acoustic guitar. For these reasons, I always suggest that kids and women learn on an electric guitar.
Yes, there are a few smaller-sized acoustic guitars out there (I use a small Yamaha guitar in some of my YouTube videos) but they don’t sound as good as a full-size acoustic, and the action is still higher than on an electric guitar. I’ve listed some small guitars on the Guitar Gear page.
Many folks living in apartments or sharing houses with other people play electric guitar because they can practice more quietly on an electric guitar, either unplugged, or with headphones plugged into their amplifier. Of course, if you decide to go electric, you will need not only the guitar but an amplifier and a cable to connect the guitar to the amplifier.
For a lot of folks the style of music they want to play is played on an electric guitar, so it makes sense to play the instrument used to create that music. There are many different types of electric guitars used to play different styles of music, so research the instruments that your favorite musicians play.
Regardless if you chose to play electric or acoustic guitar, I encourage you to purchase a guitar from a music store. That way, if it needs any adjustments, you can take it back to the store to have them repair the guitar. (A lot of times they do that for free.) Here in Seattle, I recommend The Guitar Store.
One more thing – Make sure that you buy a guitar that you really dig, not just one that is on sale. You are going to spend a lot of time with your guitar, so you want to have a guitar that you find attractive and you can really love playing.