also differs by vowel length and final consonant sounds, which can be divided into the "checked" and "unchecked" syllables. Checked syllables are a group of syllables with the obstruent coda sounds [p̚], [t̚], [k̚], and [ʔ] (short vowel with no final consonant actually ends with the glottal stop, but often omitted). The unchecked syllables are a group of syllables with the sonorant coda sound [m], [n], [ŋ], [j], and [w]. Hence, by combining the consonant classes and the system of checked–unchecked syllables, the full tone conjugation table can be constructed as shown below. Color codes are assigned in the table to each tone mark: cyan - no tone mark; yellow - mai yo (equi. Thai mai ek); pink - mai kho jang (equi. Thai mai tho). Low class and high class rows are paired together to show the system of the consonant couples. Notes Numerals Lanna has two sets of numerals. The first set, Lek Nai Tham, is reserved for liturgical purposes. The other set, Lek Hora, is used in everyday life. Relation with other scripts Tai Tham is very similar in shape to Burmese script since both are derived from Old Mon script. New Tai Lue is a descendant of Tai Tham with its shape simplified and many consonants are removed. Thai script looks distinctive to Tai Tham but covers all equivalent consonants including the 8 additional consonants as Thai is the closest sister language to Northern Thai, Khuen, and Lue languages. A variation of Thai script (Sukhothai script) called Fakkham script was also used in Lan Na to write Northern Thai, Khuen, and Lue during the 14th century, influencing the development of the modern Tai Tham script. Sanskrit and Pali The Tai Tham script (like all Indic scripts) uses a number of modifications to write Pali and related languages (in particular, Sanskrit). When writing Pali, only 33 consonants and 12 vowels are used. Pali consonants in Tai Tham script Sanskrit consonants in Tai Tham script Unicode block Tai Tham script was added to the Unicode Standard in October, 2009 with the release of version 5.2. The Unicode block for Tai Tham is U+1A20–U+1AAF: Fonts Supports for Tai Tham Unicode font in Microsoft Windows and Microsoft office are still limited causing the widespread use of non-Unicode fonts. Fonts published by the Royal Society of Thailand and Chiang Mai University are also non-Unicode due to this problem and to maximize