International House of Pancakes
IHOP was established in 1958 as the International House of Pancakes.
From 1995 to 2003, this logo was used simultaneously with the next, more simplistic logo. In 2003, it was gradually phased out in favor of the next logo. It is still used at a few scant locations.
Similar to the previous logo, except the "International House of Pancakes" wordmark was simply replaced with the acronym "IHOP". This logo would go on to be the longest used for the company, lasting for 21 years. It is still used at some locations.
In June 2015, IHOP changed its logo for the first time in 21 years, with a logo containing a curve under the 1994 wordmark resembling a smile (the "O" and "P" are the eyes while the half of "P" serves as the nose). This change was rumored to be made in order to make IHOP look "happier", as if the former was "frowning".