You may think that that hole was put there to keep a pen from drying out, but that is not the case. The hole is actually there to lower the risk of suffocation. If a child or pet accidentally swallows the pen cap, the hole will keep the airway from closing up completely.
That diamond on your backpack is not just there for decoration. This is called a “lash tabs” or a “pig snout." This diamond is intended to hold any extra gear on cords that can be strung through its openings.
In most pairs of jeans there are these little metal circles at the top corners of the pockets. They look like little snaps, but they are actually rivets. They are there to reinforce the seam where the pockets attach so they don't tear.
There is a reason why beer bottles are shaped the way that they are. Our hands carry heat, so when we hold onto our beer, we are warming up the beer in the bottle. The necks of the bottles are meant to help us keep our beer cooler. If we grab the top of the bottle at the neck when we drink, the beer on the bottom will stay cooler for longer.
Have you ever noticed that little hole in the window of an airplane? That is called a "bleed hole" and it is wedged between two other window panes made of acrylic. The bleed hole is there to equalize the air pressure from both the inside and the outside of the airplane.
Have you ever wondered why a golf ball has all those little dimples? Those ridges are there to reduce the amount of drag when the ball is flying in the air. They allow the ball to fly both faster and farther.
This tiny hole is there for a two different reasons. First, it is there to help if the lock ever gets rusty and needs to be oiled up. It is also there as a drain. If any liquids get into the lock, this a perfect way to help them drain out.
Are you driving a car that isn't your own? Have you ever gone to get gas in a rental car and you have no idea which side the gas tank is on? Well, next time this happens, look at the little arrow on the gas gauge. It will steer you in the right direction.
Next time you get a bottle of water, look under the cap. You may find a little disc under the cap that is there to help seal in both the liquid and carbonation. These discs will help your soda from going flat too quickly.
You may have noticed that in some wooden toothpick designs, there are these indentations on the other side of the pick. That is not just for decoration. If you break that part off, you can use it as a holder for hygienic purposes. Who knew?
Are you eating Chinese food on the go? Well, a Chinese takeout box is actually designed to unfold into a plate. This way you can eat your fried rice anywhere you please, whether you want it out of the box or on your new makeshift plate.