Poly means many

mer means molecule or the repeating unit.

Polymer is a single large molecule formed when a large number of small molecules come together and bond chemically to form a single large product and the process is called as polymerization.

There are two different basic reactions involved in polymerization

1) Addition polymerization

2) Condensation polymerization

Examples of these two types are tabulated below for ease of readability and recall. You just need to browse through them regularly so as to be able to remember them easily.

Best for you would be to draw them yourself with coloured pens so you can recall each by its colour. You can also stick pictures of their samples corresponding to their use. I know it sounds a tedious task but you will appreciate this hard work of yours when you see the result.