It's the only day of the year where monkey business is celebrated – Monkey Day, which falls on December 14 every year was created in a bid to raise awareness of humans' distant cousins. Despite the name, the day isn't just for monkeys, but all primates, such as apes, lemurs and tapiers.

Monkey Day is still in its infancy, having only been created in 2000. However, it quickly gained popularity and in 2005 King Kong was released on the unofficial holiday's fifth anniversary.

To mark the occasion, IBTimes UK brings you a gallery of the best monkey pictures.

Francois Langur
Taronga Zoo, Sydney

This Francois' langur was born in Taronga Zoo in Sydney on 7 November. Infants of this rare monkey are born with bright orange hair, and the ability to strike a nonchalant pose. This little fella, named Nangua, doesn't care that you are jealous of his mother.

thailand orangutans
Athit Perawongmetha/Reuters

Orangutans share 96.4% of our genetic make-up, making them one of the closest things to us in the animal kingdom. You'd be able to tell that by this extant great ape, who looks as if he is giving someone who is speaking too loudly on the tube the death stare.

Yawning Japanese macaque monkey
Daisuke Tashiro

This Japanese macaque monkey is not afraid to let you know that you are boring him by sarcastically yawning at you mid-sentence. The Japanese macaque is the most northern living non-human primate and also survives in the coldest climate of all of its hairy relatives.

Getty Images

No one told this monkey that eating sugary treats like this are bad for your teeth. Better dental education for monkeys, we demand at IBTimes UK. The rhesus macaque are found around Asia, and their impressive reproduction rates means that they are not endangered − yet.

Animals of 2014 - Macaque snow monkeys
Issei Koto/Reuters

"I'm just trying to relax, Linda. Ted from HR is giving me a lot of grief at the office and I don't need you picking at me."

monkey mirror
Neng Gong and colleagues/Current Biology 2015

Adele takes inspiration for her next album cover as the monkey stares pensively into the mirror, wondering what happened to her youthful looks. Despite what Guns N' Roses say, the jungle is not all fun and games and it will age you considerably.

western lowland gorilla

"I'm nuts, mate. I eat rocks and I WILL eat you! Someone hold my Stella." There are four subspecies of gorilla, which are the Grauer's gorilla, the mountain gorilla, the western lowland gorilla and the Cross River gorilla. The population of all of these are declining due to human interference such as deforestation.

Photos: Chimpanzee Feeds Milk to Tiger Cub

Look how pleased this chimpanzee is with itself that it can feed a less-intelligent being. Also, where did it get its trendy jean-shorts from? Chimpanzees are our closest living relatives, sharing about 98.6% of our DNA. If only it had that final 1.4%, it probably wouldn't spill milk all down itself and the tiger.

A male chacma baboon sits in the Cape peninsula outside Cape Town, South Africa

This male chacma baboon looks as if it is ready to be extensively interviewed for the Humans of New York page. Chacma baboons have lived on the Cape peninsula for around 1 million years, but their population there has decreased to just 250 in 11 troops. However, the species is thriving elsewhere and its population is of least concern.

Chap, dressed in a Santa Claus outfit
REUTERS/Yuriko Nakao

Merry Christmas.