In a Default Text Box in Objects and Animation the “Box” will expand vertically and horizontally according to the amount of text which is input

Note that the Text Box in the above example is “Anchored” around the Centre Point of the Box and therefore expands both Vertically and Horizontally about the Centre

Moving the “Centre Point” to the top of the Text Box changes the way in which the text expands

Note that while the Text Box still expands Horizontally it only expands Vertically in the Downward direction

Moving the “Centre Point” to the top left corner of the Text Box and the Alignment to “Left”

Note that the Text Box expands Downwards and to the Right of the Anchor Point

The Alignment is set to LEFT