Hornbook and Overture

Hornbook noun - A primer that provides instruction in the rudiments or basic skills of a branch of knowledge.

Overture and hornbook are semantically related. in something new topic. In some cases you can use "Overture" instead a noun "Hornbook".

Overture noun - A performance, activity, or event that precedes and sets the stage for the main event.

Hornbook and overture are semantically related. Sometimes you can use "Hornbook" instead a noun "Overture".