Yatzy is the dice game the world knows as Yahtzee: five dice, three rolls per turn, and a scorecard of combinations — pairs, straights, full houses, and the big one, five of a kind.
The skill is entirely in which dice to keep between rolls and which category to spend a mediocre turn on. Every category can only be used once, so a bad roll always has to go somewhere.
Three per turn, holding whichever dice you want between them.
A bonus for scoring enough across the number categories (ones through sixes). Chasing it early is usually worth more than an extra combination later.
Effectively yes — Yatzy is the Scandinavian version of the same dice game, with minor scoring differences depending on the variant.