Curves provide a simple but efficient method to define a deformation. Blender now supports this, like for Lattices or Armatures, by parenting an object to a curve (Ctrl P), the menu now provides a new option for it.

Unlike a Lattice or Armature, which deforms based on changes from a 'base' position, the Curve deform works on a dominant axis (X, Y, Z) which is wrapped on the curve itself.

The default settings in Blender map the global Y axis of an Object on the curve, and global Y motion moves the Object over the curve itself.

Settings to be aware of:

• Cyclic on/off
  (In editmode, Ckey) Cyclic curves will work as expected, where the Object translation will move just along the path in cycles too.
  Note that without cyclic, an object will move on based on the direction vector of the curve endings.
  
  
• Set dominant axis
  This is a reused setting in the Object Context buttons (F7), the "Track X, Y, Z" buttons. Note that this has to be set for the deformed Object
  
  
• Curve Stretch
  In Editing Context (F9) buttons for the Curve; this option stretches or squeezes the dominant axis of the deformed object over the entire curve.
  
  
• 3D on/off
  In Editing Context (F9) buttons for the Curve; this will allow to make 3D curves. It has the same limitations as for 'curve follow', where you have to avoid a straight line up in the Z direction to prevent flipping.

Curve deform now only works on Meshes. For Armatures it will be looked at.