There are three main types of glue adhesives used on book bindings, and while professional book binders have very specific preferences about which type is best, the choice can seem daunting for a novice. The following list should help you decide which glue is best for the project you are working on.
Polyvinyl acetate (PVA) is the most common of the glues. It is the everyday white or yellow glue on craft tables and in classrooms everywhere. PVA is a very strong non-toxic glue and is widely used both on its own and mixed with other adhesives. Its disadvantage is that it can be stronger than the paper that it is gluing together, so in particular when working with older books and artifacts, professional book binders tend to choose an alternate adhesive or mix a combination of PVA and another adhesive.
White PVA has a longer shelf life than yellow PVA.
Animal or Hide Glue
This glue comes from boiling animal tissue. You do not have to boil your own animals: simply purchase the powder online and mix your own. One of the strengths of animal glue is that it is reversible. This means once applied, you can re-heat it, readjust and fix a mistake you may have made. It also has a very quick setting time and doesn't need pressure to glue like a PVA does. Because of this, it can be injected into cracks easily, for example in musical instruments.
Wheat paste glue is made simply by mixing flour and water. Its advantages are that it is non-toxic and very easy to make. Amateurs should be careful to make sure they are using a low gluten flour such as a cake flour; otherwise, over time the wheat paste will attract insects. Another disadvantage to wheat paste is that once mixed it only lasts for two or three days.
Many professional bookbinders will use a combination adhesive which combines either animal or wheat paste with PVA. The PVA adds strength to either of the other two adhesives.
Hot glue guns are not recommended for usage in book binding projects.