Mazda Motor introduces the company's concept vehicle, Taiki during the press day of the 40th Tokyo Motor Show at Makuhari Messe, on October 24, 2007 in Chiba Prefecture, Japan. (Photo by Koichi Kamoshida/Getty Images)

Judy, a black collie whose owner was killed by a train when trying to retrieve her after she slipped her lead. (Photo by Evening Standard/Getty Images). 17th December 1976

Two children jumping through a water hydrant's shower on a New York street. They have come from a neighbouring co-educational playgroup organised by the city's Police Department. (Photo by Orlando/Getty Images). 1950

Hasty Pudding Theatricals Woman of the Year Sandra Bullock gets kisses from Vice President John Blickstead (L) and President of Hasty Pudding Theatricals Clare Putnam (C) in Harvard Square February 12, 2004 in Cambridge, Massachusetts. (Photo By Douglas McFadd/Getty Images)

A steam traction engine with a broken rear axle in Pall Mall, London. (Photo by Topical Press Agency/Getty Images). November 1923

With more than 40,000 followers on Twitter and 26,400 fans on Vine, it looks like Marutaro the hedgehog from Japan is one of the most popular hedgehogs on the Internet. And as his owner keeps on posting Marutaro’s pictures online daily, Marutaro’s popularity continues to grow. There are hundreds of cute photographs and videos of this little fellow, but the ones with little paper cut-out faces are probably the cutest. As Marutaro lies on his back, his owner gives him a variety of silly expressions and smiles. The 20 best of them will definitely boost your mood!

American soldiers leaping from an armoured personnel carrier during exercises in Korea, 17th March 1954. (Photo by Three Lions)