Curable adhesives is the term used to describe a large category of adhesive chemicals which require some sort of reaction within the chemicals of the adhesive to harden and form a bond.  Under storage conditions, these reactions are prevented from happening in some way, depending on what adhesive type is being stored.  The two main categories of curable adhesives are single component and two component. 

For single component adhesives, the chemical composition is fully formed and only an environmental influence is required to initiate curing.  A two component is most commonly known as an epoxy.  This is made by storing two chemically reacting formulas separately then joining them when curing is desired.

Single component adhesives have many ways of being cured.  Often a lack of oxygen will start the process.  Some adhesives require a high temperature before it will form the bond.  Commonly, many household glues also utilize moisture in the air for this purpose, as is common with the famous brand, Gorilla Glue. 

Two-component adhesives often offer a wider range of uses and have stronger bonds. For many epoxy compounds, they also cure very quickly since the process of mixing two reactive compounds together manually drives up the speed considerably.