It is never too early to start reading with your child!
Young children have the ability to retain large amounts of vocabulary (this is why children can learn languages much more easily than adults). Board books are thicker than normal books, easier for small hands to handle and durable so they don't tear easily!
Board books are ideal for children aged 0-6 years. However, quite a few board books are suitable for older children too (such as the Prophets of Islam series and the book of geography).