Acid free
Acid will ruin your pictures. If your paper is not acid free, or if anything acidic touches your pictures it will corrode then and they will be destroyed
Adhesive
This is basically your glue. Glue sticks are the most common thing for a beginner scrapbooker to start with. There is also spray adhesives, Glue pens, and adhesive tape
Album
A book with blank pages for making a collection of memorabilia, pictures, etc.
Album extender
There are posts that similar to a screw, for post bound albums that extend the bounding, which enables you too add more pages to your scrapbook.
Card stock
A thick paper similar to construction paper
Crop
Cut your pictures in order to put them into your scrapbook to make the main object stand out
Eyeletes
Little round circles that are on your shoes that you put your shoe laces threw, they add a nice dimensional touch to your pages.
Journaling
Any writing or story that you include on your pages
Layout
The page or pages that you work on involving one theme with a total, pictures, journaling and embellishments all related to one theme
Lignin
The acid found in woody plants which can break down your photos and turn them yellow and brittle. The best example is an old newspaper. The yellowy cast and very brittle pages are the results from lignin
Page protector
The plastic covering(sleeve) that protects your pages