MSG(MANAGEMENTSTUDYGUIDE.2559 : ออนไลน์) Written communication has great significance in today’s business world. It is an innovative activity of the mind. Effective written communication is essential for preparing worthy promotional materials for business development. Speech came before writing. But writing is more unique and formal than speech. Effective writing involves careful choice of words, their organization in correct order in sentences formation as well as cohesive composition of sentences. Also, writing is more valid and reliable than speech. But while speech is spontaneous, writing causes delay and takes time as feedback is not immediate.