A tetromino's orientation, with regards to Tetris refers to the different ways that tetromino can exist after rotations.

Normally all the tetrominoes have a total of nineteen orientations, but probably to make things more symmetric, newer games add six orientations: two for S, Z, and I.

Orientations can be described either by the way they point (especially for T, which at least one reviewer has compared to a finger gesture[1]) or by the way the longest flat side faces.

Point up Flat down	Point right Flat left	Point down Flat up	Point left Flat right