The Zanabazar Square script is also known as the Mongolian Square script. It is named after its creator, Zanabazar, the first spiritual leader of Tibetan Buddhism in Mongolia, who also developed the Soyombo script. The script has also been called the Mongolian Horizontal Script or Xawtaa Dorboljin. It was used for writing the Mongolian, Sanskrit and Tibetan languages. The Zanabazar Square script was inspired by the Tibetan script and has graphical similarities to Phags-pa and its variant forms.

The Zanabazar Square script is an abugida. Consonant letters bear an inherent vowel, which can be changed by writing a vowel diacritic above, below or alongside the consonant. Only the vowel /a/ has its own independent letter. Other independent vowels, for example those at the start of a word which don’t have a consonant to attach to, are written using the letter a with the appropriate vowel diacritic attached to it. There is also a vowel length mark which is written after the vowel to indicate a long vowel.