When you're out and about and desperate for the loo, venturing into a public toilet is the only solution.
They're not all bad, but the experience is certainly not as comfortable as the one you'll have in the safety of your own home.
You may have noticed there are a few design differences in public toilets while you're sat there doing your business, alongside five other people in the adjacent cubicles.
And it turns out there is a reason behind why a chunk of material is missing in public restrooms.
The idea behind switching up the design for public toilet seats is mostly down to hygiene.
This code for toilets goes back nearly 70 years to 1955 when it was first created.
It was then further commissioned by the Uniform Plumbing Code in 1973, which allowed the U-shaped toilet seat to go mainstream.
The code says: "Water closets shall be equipped with seats of smooth non-absorbent material. All seats of water closets provided for public use shall be of the open-front type."
The whole idea behind this is obviously hygiene, as the amount of people sitting on a public toilet seat in any given day is not a number we'd like to know.
But with these U-shaped seats, there is less surface area for germs to thrive, so less contact made with your nether regions.
The toilet seat was also apparently designed with women in mind.
Lynne Simnick, senior director of code development at the International Association of Plumbing and Mechanical Officials told Slate that the open seat was designed to let women 'wipe the perineal area after using the water closet' without using a seat that might be unhygienic.
Simnick also added that the open-front seat 'eliminates an area that could be contaminated with urine', while it also 'eliminates the user’s genital contact with the seat'.
Before this, many people speculated on the reasoning behind the odd-looking toilet seat.
According to Slate, some of the theories as to why the seat is used included men apparently being less careful in public toilets, and the U-shaped seat may be cleaner than the traditional oval if it isn't raised.
Other theories said people being afraid of catching STIs from public toilets and the U-shape seat being easier to clean as contributing factors.