A tagline is a slogan, a memorable phase that conveys the message of the company and evokes the essence of the brand. It should be unique and differentiate the company from the competition.
A descriptive tagline can add clarity to an otherwise ambiguous name such as Google which acquired the tagline "Search, Ads and Apps" in 2007.
The tagline can change over time. Here are just four of Apple's taglines:
The Computer for the Rest of Us
Get a Mac
Allstate - Your in Good Hands
American Express - Don't leave home without it
Avis - We try harder
Bounty - The quicker picker-upper
Clairol - Does she or doesn't she?
Energizer Batteries - It keeps going, and going, and going...
General Electric - Imagination at work
Kentucky Fried Chicken - Finger-lickin' good.
L'Oreal - Because I'm worth it
M&M Candies - Melts in your mouth, not in your hands
New York Times - All the news thats fit to print
Nike - Just do it!
Prudential - Get a piece of the rock
Yellow Pages - Let your fingers do the walking