The Liquify tools offer several ways to distort the image:
Warp
pushes pixels forward as you drag.
Turbulence
smoothly scrambles pixels. It is useful for creating fire, clouds, waves, and similar effects.
Twirl clockwise
rotates pixels clockwise as you hold down the mouse button or drag.
Twirl counterclockwise
rotates pixels counterclockwise as you hold down the mouse button or drag.
Pucker
moves pixels toward the center of the brush area as you hold down the mouse button or drag.
Bloat
moves pixels away from the center of the brush area as you hold down the mouse button or drag.
Shift pixels
moves pixels perpendicular to the stroke direction.
Reflection
copies pixels to the brush area.
Clone
copies the distortions from around a source location to the current mouse location. Select the source location by Alt-clicking (Windows) or Option-clicking (Mac OS) the source point.
Reconstruction
reverses distortions or applies them in different ways.