Ukuleles may look like tiny guitars, but there are some key differences. For one thing, they have four strings, while most guitars have six. The strings, too, are made of nylon, which gives a warm, soft tone; most guitars use metal strings (though the Spanish guitar also uses nylon). Ukuleles are also tuned differently, using what’s called an “open” tuning. Strumming a ukulele without touching the frets will play a nice chord, and ukulele playing relies more on one or two fingers than guitars, which are often strummed with four.