What’s in a name? In the case of Taco Bell, the name includes the surname of its founder, Glen Bell (1923-2010).

A serial restaurant owner, Bell operated multiple restaurants in California during the 1950s, including two in San Bernardino: Bell’s Drive-In, and Bell’s Hamburgers & Hot Dogs. Bell had heavy competition in the San Bernardino hamburger market; the town was also home to the first McDonald’s.

In order to differentiate his own eateries in the area, Bell decided in 1951 to start selling hard-shell tacos, instead of hot dogs or burgers. After various Mexican food-related enterprises, including a chain called El Taco, Bell opened his first Taco Bell in 1962 in Downey, California. By 1967, there were 100 Taco Bell restaurants nationwide, and in 1978 PepsiCo bought 868 Taco Bell locations. In turn, Glen Bell became a PepsiCo shareholder. As of 2018, Taco Bell was serving over two billion customers each year, at 7,072 restaurants. Over 93 percent of the locations were owned and operated by independent franchisees and licensees.

Jack in the Box was founded in San Diego 1951 by Robert O. Peterson.

Wendy’s was founded by Dave Thomas in Columbus, Ohio, in 1969. He named the chain after his daughter, Melinda "Wendy" Thomas.

Arby's was founded in Boardman, Ohio, in 1964, by Forrest and Leroy Raffel, owners of a restaurant equipment business. The chain denies that its name was derived from the letters R & B (a reference to their signature Roast Beef sandwich).

More Info: en.wikipedia.org