Tasbih

They are the muslim prayer beads. They are similar to the Greek worry beads, and there is a Buddhist equivalent too.
The way you use them: you pronounce each of four names of God 33 times, plus 1.


Subhan’allah (Glory be to Allah)
Alhamdulillah (Gratitude be to Allah)
Allahu Akbar (God is the greatest)
Laa Ilaha Illa Lohu (only once: there is no other God than Allah).

Another way to keep the count is to use your finger phalanges (3 for each finger and then repeat one thumb).
A third way, quite less romantic and fascinating, is a mechanical counter (you push a button each time). But it makes sense for old people with arthritic hands.