Does short message belong to literature? If it is literature, what kind of literature does it belong to? How many types of short messages are there?

I can understand it as practical writing (letter). Including prose, poetry, prose, etc.

Short Message Service (SMS for short) refers to the text or digital information directly sent or received by users through mobile phones or other telecommunication terminals. The number of characters that users can send and receive SMS at a time is 160 English or numeric characters or 70 Chinese characters.

According to different objects, different times and different purposes, short messages are divided into the following categories: 1. Holiday greetings and blessings: birthday, Spring Festival, New Year's Day, Mid-Autumn Festival, National Day, Christmas, Teacher's Day, Mother's Day, Father's Day and so on. 2. Major events: successful Olympic bid, shenzhou spaceship, SARS, etc. 3. Express feelings such as missing: parents, children, friends, classmates, etc. 4. Business contacts: meetings, negotiations, thanks, etc. 5. Entertainment, humor, etc.