Uyghur script

Uyghur is a Turkic language with a long literary tradition spoken in Xinjiang, China by the Uyghurs. Today, the Uyghur Arabic alphabet is the official writing system used for Uyghur in Xinjiang, but other alphabets - the Uyghur Latin and Uyghur Cyrillic alphabets - are still in use, especially outside Xinjiang.

The Old Uyghur language and Modern Uyghur are distinct Turkic languages and are not different stages of the same language. The Old Uyghur language is ancestral to Western Yugur, while modern Uyghur is descended from one of the Karluk languages.

In the 5th century Old Uyghur was written for the first time using the Sogdian alphabet. This fell out of use during the 10th century, when it evolved into the Old Uyghur alphabet, although it was taken into use again between the 15th and 16th century. While the Sogdian alphabet was still in use, it was written with the Old Turkic alphabet from the 6th-9th centuries.

The Old Uyghur language evolved into the modern Western Yugur, and remained in use until the 18th century among the Yugur.

An Arabic alphabet introduced along with Islam in the 10th century to the Karluk Kara Khanids, which evolved into the modern day Uyghur Arabic alphabet.

The Arabic-derived alphabet taken into use first came to be the so-called Chagatai script, which was used for writing the Chagatai language and the Turki (modern Uyghur) language, but fell out of use in the early 1920s, when the Uyghur-speaking areas variously became a part of, or under the influence of, the Soviet Union.

...
Wikipedia