Synthetic phonics is a method of teaching reading that starts with basic letter sounds, blending and sounding out words. It is most often used in the very early stages of learning to read, before students are able to recognize any words by sight. This differs from whole language or analytical phonics methods, which emphasize sight words and book reading over sounding out words.
The process of synthetic phonics generally begins with learning to decode and encode individual letter sounds. At this early stage of phonics learning, decoding refers to recognizing a letter and identifying the sound it makes. Encoding refers to hearing a sound and knowing what letter represents that sound. Decoding and encoding are the basic skills necessary for phonics-based reading and writing, respectively.
After learning to decode and encode individual sounds, students are taught how these basic letter sounds combine to make words. At this stage, students should be able to sound out, or decode, simple three-letter words and sentences made up of three-letter words. For example, the sentence "Jim and Hal sat" contains only words that follow very simple phonetic rules. Students are eventually taught sound blends, such as /th/ and /sh/, and then learn to sound out more complex sounds.
Only when students have mastered these basic phonetic concepts are they taught high-frequency sight words, such as "said" or "one," that cannot be sounded out. Since so many common English words fall into this category, students being taught according to the synthetic phonics model usually are not able to read even very simple books early on. Students only progress to reading books once they have a solid grasp on a large number of phonetic rules.
Other methods of teaching reading, such as whole language and its variants, reverse this process. Whole language begins by teaching sight words as they are encountered in book reading. This method is often combined with analytical phonics, in which students learn phonetic rules by analyzing words that they already know. For instance, students would learn the word "cat" by seeing it and hearing it read repeatedly in the context of a book or story. They would then be taught that the individual letters in the word "cat" correspond to the sounds /k/, /a/, and /t/.
Educators will often combine aspects of several different approaches to reading. Synthetic phonics is very useful for pre-literate students who are not yet able to recognize any words by sight. Once they have learned some basic phonics rules, students may increase their reading fluency by recognizing words without needing to sound them out.