What is the meaning of Switcher?

One who or that which operates a switch.

One who or that which switches, that is, changes in some way.

A switchmode power supply.

A railway locomotive used for shunting (switching).

The yardman who operates such an engine, or performs a similar role in a trucking depot.

Synonym of vision mixer (“device for selecting between video sources”).

to switch (clarification of this definition is needed.)

Source: wiktionary.org