McDonald's is one of the largest and most recognizable restaurant chains, globally known for signature menu items like the Big Mac and Chicken McNuggets.

But 30 ages ago, the fast food giant was also known for its commercials and products featuring iconic characters like Ronald McDonald, Grimace, and the Hamburglar.

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McDonald's launched "McDonaldland," a fantasy biosphere used in commercials to appeal to kids, featuring the characters Ronald McDonald, Grimace, Hamburglar, Sundae, Birdy the Early Bird, Mayor McCheese, Officer Big Mac, Captain Crook, and the Professor, according to IMDB.com.

The business began airing the McDonaldland commercials in 1971. But in 2003, the business slowly phased out the characters as it changed its marketing campaigns to engaging to more adult consumers, the Daily Meal noted. 

Who were the characters?

Ronald McDonald, the best known of the bunch, was a wicked clown with red hair and lipstick dressed in a yellow outfit complimented by red shoes. Famed TV weatherman Willard Scott was among those to wear the iconic clown suit back in the 1960s.

Grimace was a purple describe who debuted in commercials as "Evil Grimace," a bad guy who tried to hold McDonald's shakes but was later rebranded as a good guy by the business, according to the Daily Meal.

Hamburglar was the fast food thief dressed in dark and white stripes, wearing a black mask. The describe was known for stealing hamburgers from Ronald McDonald and his friends.

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The Fry Kids characters promoted McDonald's French fries and were famous for taking and eating the other characters' fries.

Birdy the Early Bird dressed like an feeble aviator in a flight cap and scarf. The describe promoted McDonald's then-new breakfast menu to young consumers.

Mayor McCheese had a hamburger for a head and wore a top hat, and sash with "mayor" on the precedent, and a pair of small glasses.

Officer Big Mac was a police officer downright obsessed with stopping both Captain Crook and the Hamburglar.

Captain Crook was a pirate who later reached "The Captain" and was known for trying to select Filet-O-Fish sandwiches in commercials.

The Professor, a bearded scientist with a lab coat, was McDonaldland's inventor and researcher.

Why did McDonald's phase out Ronald McDonald?

McDonald's allowed to curtail the use of Ronald McDonald in campaigns due to reports of creepy clown sightings six existences ago, the Associated Press reported. 

In 2016, McDonald's said it was populate "thoughtful in respect to Ronald McDonald's participation in shared events" as a result of the "current climate throughout clown sightings in communities." 

The AP noted that McDonald's didn't allotment any other details about how often Ronald McDonald made appearances, and how it changed.

According to the AP, the burger chain made its decision-making after a series of pranks around the country inspiring eerie clown sightings. The reports have forced police in some areas to respond.

Ronald McDonald is now picture on Instagram, promoting McDonald's and the Ronald McDonald House charities. 

In 2022, McDonald's revived the beloved characters from McDonaldland with the initiate of an adult Happy Meal featuring toy figurines: Grimace, the Hamburglar, and Birdie and Cactus Buddy. 

FOX 9 Minneapolis, FOX 32 Chicago, and the Associated Press contributed to this picture. This story was reported from Washington, D.C.