Children typically use smaller string instruments than adults. Violins are made in so-called fractional sizes for young students: Apart from full-size (4/4) violins, 3/4, 1/2, 1/4, 1/8, 1/10, 1/16, 1/32 and even 1/64-sized instruments exist, although these smaller sizes are highly unusual and usually custom-made.
The modern banjo comes in a variety of forms, including four- and five-string versions. A six-string version, tuned and played similarly to a guitar, has gained popularity.
Mandolins have a long history, and much early music was written for them. In the first half of the 20th century, they enjoyed a period of great popularity in Europe and the Americas as an easier approach to playing string music.