The human brain may be fragile and mushy, but we simply couldn't live without it.
Made up of a complex network of cells called neurons, the brain is the body's most complicated organ, and also the most important. This massive ball of tissue inside your skull is responsible for directing your entire body, including breathing and movement.
But for something so important, there seems to be an awful lot of myth and misinformation.
So for some grey matter guidance, Young Post picked the brain of the chairman of the Association of Brain-based Learning in Education, Ricky Chan.
In Scarlett Johansson's latest film, Lucy, the heroine becomes a mind-reading, telekinetic warrior after she accidentally takes a drug that lets her use the full power of her brain.
The transformation is so dramatic because the film says the average person actually only uses around 10 per cent of their brain's power.
But do we really all possess so much untapped potential just waiting to be put to use? Sadly not, according to Chan.
"It's definitely a myth," he says. "It's a nice myth, but it's a myth all the same."
Using all of our brains is, in fact, well, a no-brainer. Like other organs, the human brain has been developed over millions of years of evolution. There would have been no benefit to evolve a brain that we didn't properly use.
In short, yes they are.
"It's something very close. The human brain is roughly 77 to 78 per cent water," says Chan.
"Our brains require water to function properly. Water is one of the main components of the liquid surrounding our brains, which is critical for its development and also for its safety."
Neurons, the cells in our brain responsible for processing and transmitting information, store water in tiny balloon-like structures called vacuoles. They require a delicate balance between water and various other elements to function well.
Water also keeps the brain from overheating. Studies have shown that water is so important to the brain that dehydration can cause tiredness, a decrease in focus and short-term memory loss.
Although the brain doesn't directly generate electricity, it can do so indirectly through a type of chemical signalling.
"The brain uses different types of energy," says Chan. "It uses chemical energy ... to send messages. When we think, neurons have to use chemical energy to communicate, and through this process, generate electric energy.
"If we use most of the areas of our brain at once, then we will be able to produce enough energy to light up a light bulb."
But don't worry, it's unlikely we are all going to be plugged into some sort of Matrix-like machine any time soon.
Geniuses in cartoons or sci-fi films often have giant brains, but bigger doesn't always mean better.
"It is not necessarily the larger size of the brain that contributes to higher IQ, but the size of the different regions of the brain," says Chan.
Chan adds that the two main things that contribute to intelligence are the complexity of the neuron connections and the level of development of the areas most important for thinking.
So in short, size doesn't matter. Lighten up, you don't have to have a huge head to be top of the class.