In language, a digraph is two letters or characters that make a single sound when pronounced, also known as a phoneme. The sound made by the digraph is usually noticeably different than the pronunciations of the individual letters would be. Around the world, many languages have their own sets of unique digraphs. In the English language, knowledge of the assorted digraphs is considered to be essential in learning how to read. It is important for students to be able to recognize these sounds since they can't be decoded using standard phonics rules.
Languages all over the world are composed of distinct sounds called phonemes. Each spoken phoneme has a written equivalent so that, when a reader sees the letters or characters, he or she knows which sound to pronounce. In most cases, each sound, or phoneme, is represented by a single letter; however, in some cases, the phoneme is represented by two letters together, called a digraph. Another feature of a digraph is that the phoneme that it represents usually sounds very different than what would be expected based on the sounds of the individual letters.
Many languages utilize digraphs composed of two letters or characters, depending on how the language is written. In these languages, the digraph is used to express a distinct sound that is unique and can't be written any other way. In some, the digraphs also have a place in the alphabet because they can't be separated into separate sounds. An example is found in the Czech language where the digraph -ch makes a sound similar to the English -x, and has its own spot in the alphabet. In other languages, the alphabet only contains single letters or characters and there are also a few languages like Turkish and Serbian that do not have any digraphs.
In the modern Roman alphabet, also known as the Latin alphabet, digraphs can be represented by two vowels, two consonants, or one of each. Some examples of digraphs in the English language include letter combinations such as -sh which is found in words like "she" and "shop," and -th in words such as "they" and "that." Examples of digraphs that contain vowels include -aw in words like "saw" and "awful," and -ou in words such as "out" and "loud." In each of these cases, the sound produced by the letters combined is different than would be expected if each individual letter was pronounced with its typical phoneme.
When learning to read the English language, it is considered very important for students to have knowledge of the digraphs. Some are particularly vital since they appear often in the most frequently used words, which make up a large percentage of written material. A few examples of these include -th words like "the" and "with," as well as -ch words such as "each" and "which". Digraphs in a word can't be sounded out by applying standard phonics rules, making recognition of them essential for the novice reader.