The term logo originated from a Greek word called logos.  Logo is a visual sign that communicate a word or a phrase.

In the early days man used hieroglyphics to brand heir belonging. The also used court of arms to identify  nobility and houses

Before 1800s logos were marking which was used for identification process .One of the well-known  brand that still exist till today is the Cadbury logo

Over the last century  introduction of color printing which logo in advertising and making logo memorable to potential customers. This has made the them to boost popularity to many businesses.