Wax seals were typically placed across the opening of a scroll, so that only the proper person, in the presence of witnesses, could open the document. This type of "seal" is frequently used in a figurative sense, in the book of Revelation, and only the Lamb is worthy to break off these seals.

Why did we stop using scrolls?

Books have completely replaced scrolls, since books are so much easier to use. Technologies like the printing press also made it cheap to produce texts as books, but if we didn't find books superior, it would still be possible to buy versions of your favorite novels or math texts (or dictionaries!) in scroll form.

What were biblical scrolls made of?

Scrolls were made by gluing together papyrus sheets (made from the pith of the papyrus reed) or by sewing together parchment leaves (made from treated and scraped animal skins); they were written in columns and read by shifting the roll backward and forward from some wooden support on one or both ends.