Learn to see
Children learn to speak by learning to see. Each object on the page has a name. It can be pointed to and given a name. Differentiating between one thing and another (not so easy for a baby!) is called visual discrimination and it's an essential skill.
Pre-reading skills
Educators call it 'concepts of print'. It's the understanding that books convey meaning, that there is a right way to hold a book and that pages turn from left to right. Children must learn all this long before they encounter the alphabet. And cloth books are the perfect place to start.
A sensory treat
A picture tells a thousand words but a sensory experience is worth a million. What does 'furry' mean to a 6-month-old? But stroking an eskimo's hood...? Now you really understand.