Whether you have a haunted mansion, a creepy abandoned fairground or a longstanding mystery about some hidden treasure, Scooby-Doo and his friends are the people to call.

A bright green and blue van, full of teenagers along with their dog, breaks down on a foggy night. The clueless, hungry gang stops at a spooky old mansion down the road to call for help, only to find out the place to be haunted by vengeful spirits.

After hijinks ensue, a trap is sprung, and these kids, who look timid at the beginning but eventually turn out to be great detectives, discover that the ghost was actually someone who was trying to hide his crimes.

Does this story sound familiar? Of course it does! It is after all the basic storyline of Scooby-Doo cartoons that has entertained three generations of kids, and now, the franchise is celebrating 50 years since its first episode titled 'Scooby-Doo, Where Are You?' aired on CBS, September 13, 1969.

This cartoon series features Fred, Daphne, Velma, Shaggy and their talking dog Scooby-Doo who solve mysteries involving supposedly supernatural creatures.

Whether you have a haunted mansion, a creepy abandoned fairground or a longstanding mystery about some hidden treasure, Scooby-Doo and his friends are the people to call.

It has been 50 years since these youngsters have been solving clues and running up and down corridors to unmask the ghost and mysteries for viewers all around the world.

Writers Joe Ruby and Ken Spears created the original series 'Scooby-Doo, Where Are You!' for Hanna-Barbera Productions. The idea of mystery solving kids was rejected several times by CBS. Then Hanna-Barbara changed the show to star the dog instead of the humans, renamed him Scooby-Doo, and toned down the spooky elements. It was then re-pitched to CBS and the rest is history!

What started as a Saturday morning cartoon, exploded into an enormously successful franchise encompassing twelve different series, multiple films, two live-action movies, consumer products and much more.

Some versions of Scooby-Doo feature different variations of the show's supernatural theme, and include characters such as Scooby's cousin Scooby-Dum and a nephew Scrappy-Doo in addition to or instead of some of the original characters.

The franchise was nominated for two major awards but failed to win both of them. However, in 2004, it aired its 350th episode that surpassed The Simpsons' 335 episodes and Tom and Jerry's 209 episodes in popularity and views. The feat landed the show in the 2006 edition of the Guinness book of world records.

For 50 years (or 213 dog-years!), the cowardly and perpetually hungry Scooby-Doo has graced televisions across the planet all the while solving paranormal mysteries. The Great Dane with the world's most adorable speech impediment has been assuring kids that there is no such thing as ghosts and that in each of us lives a courageous identity. The skeptical nature of the show also taught youths to question everything that seems out of the ordinary and that strangers should be best avoided.

Here are some unknown facts about Scooby-Doo which you must know.

Totally too much!

The show was originally pitched differently. It was going to be called The Mysteries Five and would revolve around the ghost-hunting adventures of a rock band that toured around in a hippie van. Their names were going to be Geoff, Mike, Kelly, Linda, and W.W. with their bongo playing dog named "Too Much." But the project got rejected, and it was back to the drawing board.

W-Who's Scared?

Scooby-Doo, Where Are You! was originally named, "W-Who's Scared" but CBS thought the artwork was too frightening for children. While on the way to a development meeting, one of the producers was inspired by a line from Frank Sinatra's "Strangers in the Night" where he sings "doo-be-doo-be-doo. Hanna-Barbara changed the show to star the dog instead of the humans, renamed him Scooby-Doo, and toned down the spooky elements.

There are more Scoobys!

Scooby-Doo is one of the triplets. The other two were Dobby Doo and Skippy Doo. He has two brothers called Yabba Doo and Howdy Doo. Scooby also had a sister named Ruby Doo, who is the mother of his nephew Scrappy.

Great Dane? Sheepdog? Make up your mind!

Scooby was originally a Great Dane, but producers thought he would look too similar to Marmaduke, another famous cartoon dog, so they changed him to be a sheepdog. This ended up being too similar to Hot Dog from the comic Archie, so they settled back on a Great Dane.

Scooby's not like other dogs

Our favourite dog has a special way of talking which is not like the other cartoon dogs. But very few know that Scooby-Doo has a speech disorder. Scooby's speech disorder is called rhotacism. This is when you use the letter "r" excessively.

Scooby Snacks Still Exist

There is nothing Scooby cannot do in the name of Scooby Snacks. The snack is favourite of shaggy too. It gained so popularity that it became a real-like thing. Scooby-Doo cartoon packaging is purely a treat for humans.