The question of whether or not a noise is funny is highly subjective, as one individual may find a fart noise humorous, while the same noise can evoke disgust or embarrassment in another. While the nature of a "funny noise" is a bit unclear, human consensus has categorized some noises as more humorous than others.
An unlimited supply of funny sounds are available on YouTube, including the scream emitted by various goats. Wikipedia shares that a LaughLab study found the word "duck" to be the funniest sounding animal name. It can be argued that the quacking sound a duck makes is also odd.
Funny sounds aren't limited to verbal communication. If you're a 12-year-old pre-pubescent boy, you may find hilarity in creating fart noises with your hands. This can be done by trapping air between your hands and squeezing them together, or by placing one hand under the opposite armpit and quickly lowering that arm.
Thanks to the invention of the Internet, an array of funny noises are at available at any given time. Universally funny noises often include babies laughing, koalas fighting and whoopee cushions. Comedians can also evoke laughter, uses their voices to create funny noises while telling jokes and stories.