all about glue

[i_love_cats]

What is glue made of?
How do they make it?

[Mort_Furd]

What kind of glue?

[Tapioca_Dextrin]

Some glue is made from horses

http://www.straightdope.com/mailbag/mhorseglue.html

[Q.E.D]

If you mean casein glue, aka white glue like Elmer’s, it’s made from milk proteins.