Guys what is UMD?

[pepsik]

Guys what UMD means?

[Arkat]

Use
Magic
Device

It's a skill.

[hydra_ex]

Guys what UMD means?

Use Magic Device, arguably the most powerful skill in the game.

Using it, you can activate scrolls, and wands, such as heal scrolls, and raise dead scrolls, even if you are not a cleric. It also allows you to use items opposed to your alignment, such as true chaos/true law. It even allows you to bypass Race Required equipment.