The tradition of a wedding guest book began many hundreds of years ago. There was a need for testimony of those in attendance to the covenant of the marriage. Those signing their names would be testifying to the reality of the marriage. The book or ledger, therefore, was signed after the ceremony.
While brides and grooms in modern times generally require two witnesses signatures to the ceremony, a guest book is often used to record those in attendance at the special day as a memento.
The term “book” has taken on many forms. Brides and grooms may choose to have guests record thoughts, wishes and advice, or simply a signature, in a book form. Nowadays, however, most couples prefer a "book" they can display or use, such as a signed picture frame or signed platter. I have seen many different, unique guest book over the years. Of course my absolute, all-time favorite is the Signature Keepsakes Frame.