What is the top of a match made of?

There are two different types of matches that can be distinguished by the different match heads. With both types, the main part of a match is wood or a type of cardboard-ish paper. The wood is commonly composed of white pine or Aspen due to rigidness and workability.

Safety Matches:

These matches are designed so they will only combust when struck against the right type of surface. The match heads are composed of sulfur (this is what you smell) mixed with oxidizing agents like potassium chlorate, colorants (dyes), fillers, glue (binders), starch, and powdered glass. The glass in the match creates friction with the glass in the safety paper which ignites the head and then burns the wood.

Friction Matches:

These matches are designed so they can ignite on any surface that will produce sufficient friction. They are composed of many of the same chemicals that are in safety matches, but friction matches also contain antimony (II) sulfide, which causes the fire to burn more vigorously. Friction matches don't have the glass present in safety matches, so they can be struck on any surface.