As with other big milestones like walking or talking, there's a wide range of what's normal when it comes to how kids learn to read. But regardless of whether your 4-year-old is reading on his own or doesn't know his letters yet (and yes, both are normal), all kids progress through the same stages when learning to read.
Pre-reading (Birth to kindergarten): Before even entering school, most kids are familiar with the front-to-back, left-to-right construction of books. They may even "read" books to you, based on the pictures or their memories of the story. By kindergarten, most kids know the letters of the alphabet and that the letters represent certain sounds.
Reading and Decoding (First and Second Grade): At this age, kids pull together their understanding of sounds and letters and stories to begin decoding words. Kids in this decoding stage are often so focused on figuring out the words that they miss the meaning of a story.
Fluency (Second and Third Grade): When kids have mastered decoding, they move into the fluency stage of reading development. They're able to read more words, with expression, and they read with understanding.
Reading for New Learning (Fourth through Eighth Grade): As kids are able to read with understanding, they can focus less on the act of reading and spend more time to learn new information -- such as studying science or history at school.
To find out if your child is on track and learn how to recognize early signs of trouble, visit Reading Rockets.