Is there a difference between the words "zig", "zag", and "zigzag"?

In the book "The Green Mile" by Stephen King, a mouse is described to zig and then zag. What's the difference between the words "zigzag", "zig" and "zag"?

The mouse barley avoid Percy's last two jumps, first zigging and then zagging.

I guess I'm unclear as to the description given of what the mouse did. Is he saying the mouse first went in one direction and then went in another to avoid being jumped on?

From Wikipedia:

A zigzag is a pattern made up of small corners at variable angles, though constant within the zigzag, tracing a path between two parallel lines; it can be described as both jagged and fairly regular.

Zig and zag as separate words can both be defined as follows;

noun: a sharp change of direction in a zigzag course for example "he went round and round in zigs and zags"

verb: make a sharp change of direction for example "we zigged to the right"

The words "zig" and "zag" mean the same thing and are both derived from "zigzag". Since the word "zigzag" essentially means "moved side to side", zig and zag are often used to clearly state that something moved one way (zig) and then the other (zag).

'Zigzag' is an expression which means to dart from side to side. Sometimes people will say she zigged and then zagged, indicating she went from side to side, possibly with no apparent purpose. Taken individually the words zig and zag have no meaning, but only when used together.