Section One - Grammar and Spelling

The alphabet consists of 44 consonants (2 of which are no longer in use) and 32 vowels, the latter consisting not of an individual letter, but of a mark written above, below, before, or after the consonant with which it is pronounced. Thai also has five tonal marks; four are indicated by signs over the consonants and the absence of a sign indicates that the first tone is to be used. Words are not separated from each other and the letters generally flow uninterrupted until the idea changes.

There is no capitalisation.

Section Two - Punctuation

There is no punctuation in Thai, including full stops.

Brackets, speech marks and exclamation marks can be used in the same way as in English.

Section Three - Measurements and Abbreviations

Lengths and areas have unique measurements, but Western metric measurements are in common use.

Time: There is no equivalent abbreviation of am and pm. Times are usually just written in full, i.e. 10 in the morning, 3 in the afternoon. The 24-hour clock (e.g. 16.00 h.) is normally used in formal writing.

Date: Dates are written as 25/8/99, or 25/8/42 (which indicates B.E. instead of A.D.). The full format will be (Date) 25 August (B.E.) 2542.

Decimal points are used, i.e. 3.7%.

Numbers over 9999 are separated by a comma, i.e. 67,000.

Spaces are not to be inserted between a figure and its measurement.

Thai numerals: ๑ ๒ ๓ ๔ ๕ ๖ ๗ ๘ ๙ ๑ ๐

Section Four - Hyphenation

Hyphenation is mostly used in splitting a word over a line or to split a word into parts, each of which has a meaning.

Section Five - Miscellaneous Peculiarities

Some consonants when used as a final letter of a word will produce a totally different sound, as opposed to when they are used as an initial letter. There are many rules and exceptions to be memorised.

Section Six - Geographic Distribution

Thai is spoken by over 85 per cent of the population of Thailand, or about 50 million people. It is a member of the Sino-Tibetan family of languages, which means that it is distantly related to Chinese. It is closer, however, to Lao, spoken in Laos, and to the Shan language of northern Burma. Like Chinese, Thai is a tonal language, meaning that different tones, or intonations, distinguish words that would otherwise be homonyms.

The origin of the Thai alphabet is obscure, but it is believed to have had its origin in southern India.

Thai is spoken/used in the following countries:
Thailand, USA, Vietnam.

Language family
Family: Sino-Tibetan
Subgroup: Tai

Source: http://www.worldlanguage.com/goto/language/94.html - Copyright © Kenneth Katzner, The Languages of the World, Published by Routledge.
Useful links - http://www.royin.go.th (The Royal Institute – Thailand)

Section Seven - Character Set

g	k	k	k	ng	j	ch	ch	s	ch	y	d
ก	ข	ค	ฆ	ง	จ	ฉ	ช	ซ	ฌ	ญ	ฎ
dt	t	t	t	n	d	dt	t	t	t	n	b
ฏ	ฐ	ฑ	ฒ	ณ	ด	ต	ถ	ท	ธ	น	บ
bp	p	f	p	f	p	m	y	r	l	w	s
ป	ผ	ฝ	พ	ฟ	ภ	ม	ย	ร	ล	ว	ศ
s	s	h	l	Not sounded	h
ษ	ส	ห	ฬ	อ	ฮ

NB: 42 Consonants (not including 2 consonants which are no longer in use)

Vowel diacritics

a	aa	i	ee	eu	eu	u	oo
-ะ	-า	- ิ	- ี	- ึ	- ื อ	- ุ	- ู
e	ay	air	air	oh	o	or	or
เ-ะ	เ-	แ-ะ	แ-	โ-ะ	โ-	เ-าะ	-อ
eu-a	eu-a	ee-a	ee-a	eur	eur	er	er
- ัวะ	- ั ว	เ - ียะ	เ - ีย	เ - ือะ	เ - ือ	เ-อะ	เ-อ
um	ai	ai	ow	reu	reu	leu	leu
-ำ	ใ-	ไ-	เ-า	ฤ	ฤา	ฦ	ฦ า

NB: 32 Vowels (plus 4 vowels adopted from Sanskrit which are rarely used)