Representation of language in either visual or tactile form is known as writing. It is different from painting, cave drawing and other forms of illustration and the preservation of language through non-symbolic, non-textual media like magnetic audio tapes. Apart from raised notation systems like Braille used by visually impaired and blind, most writing systems involve the use of visual signs.
The complexity of administration and trade surpassed the power of memory by the 4th millennium BC. Political expansion and the need for a reliable method of maintaining historical records, keeping financial accounts and transmitting information is believed to have lead to the invention of writing.
Writing systems comprise of sets of symbols that signify different sounds of speech. The systems also include symbols for numerals and punctuations. A writing system may be defined as a system consisting of essentially permanent symbols used to signify an utterance in such a manner that it can be recovered almost exactly without the intervention of the speaker. The systems can be categorized into 2 types - systems representing syllables and those representing vowels and consonants. There a few systems that represent both.
A writing system needs to fulfill 3 main criteria - it should be used for the purpose of communication, it should include artificial graphic symbols on an electronic or durable surface and it should involve the use of symbols related to electronic programming or articulate speech so as to enable communication. Writing systems have functional as well as symbolic applications. They not only offer a visual method of representing language, but also represent different people and cultures. | 
