The hand, your best tool

Twenty-seven bones, no muscles in the fingers, and a thumb that changed history. How your hand works.

6 minutes · 6 stops · Supporter tour

1. Puppet strings

   There are no muscles inside your fingers. Muscles in your forearm pull on long tendons, like puppet strings, to curl them. The deepest one bends your fingertips for a strong grip.

2. Straightening up
3. The opposable thumb
4. A precise pinch
5. The fine-tuners
6. Eight little wrist bones

Start the tour in the 3D atlas