A codebook is a set of answer categories that can be assigned to one or more variables in a codingschema (for example ‘liberal’, ‘republican’, ‘other’).
To make a codebook, go to Coding->Codebooks->Create new codebook.
First, change the codebook name. Then, hover the cursor over the codebook name, and a little star icon appears. Click on this to add a new code, that is, one answer option for a particular variable, to the codebook.