A switcher, also called a matrix router, is a device that routes input signals to certain outputs. It is the most economical and traditional way to send fonts to one or more screens. There are switches of all video formats, for example there are HDMI, DVI, VGA, etc., but not only that, there are also switches for audio and other types of content. Multiple fonts can reach multiple screens but with the limitation that the switching is one by one, that is, only one font goes to each screen. With a switcher you cannot splice fonts or make a PiP (Picture in Picture), nor can you send more than one font per screen at a time.
A switcher is the way to save costs when you can't invest in a Video Processor, which has more flexibility and more versatility in its image handling.