Final answer:
A general information sign for a library is commonly referred to as a Catalog sign. It provides information about the library's catalog, which helps users locate books.
Step-by-step explanation:
The general information sign for a library is commonly referred to as a Catalog sign. This sign provides information about the library's catalog, which is a system used to organize books and other materials in the library. The catalog sign helps users locate books by providing them with the necessary information such as the book's title and Dewey Decimal number.