Type the words "sleep mask" into the search window of your favorite search engine and you will find literally thousands of people wanting to sell you one.
What is it though? And what's the use of one?
Well, a basic sleep mask would be a soft covering that is designed to fit snugly over the eyes, to eliminate any chance of external light filtering in to distract or disturb your sleep.
So what's so special about sleep masks? For one thing, it is a good way of getting some sleep in places where you may not have much choice about leaving a light on. Not everyone can fall asleep and dream under harsh and bright lights. And even for people who can, it is well accepted that the best, deepest, and most refreshing sleep occurs in a dark environment. So, if you are in a place where turning off the lights is not an option, or where there is ambient light that might disturb your rest, an eye mask for sleeping might be a good idea.
Sleep masks are great for travelers, for example. On that long haul flight, with an important power meeting looming in the morning, and with no way of getting the cozy darkness of your own bedroom, a sleep mask can make all the difference between a good morning and a bad one.
It can also be useful in places far to the north, where nights may just be a matter of clock rather than sunset. If the solar day lasts for weeks on end, sleeping might become a problem for a visitor used to dark nights. An eye mask for sleeping can be useful, in such circumstances, in eliminating the disturbing light and aiding a good night's sleep.
There are innovations on the basic design as well. A sleep mask these days is no longer a matter of just a thin double strip of shaped nylon with a layer of foam in between. Welcome to the world of silk masks and velvet masks molded to fit the contours of the face. Some even come with built-in ear pillows. These are like modified earmuffs that fit over the ears to reduce the levels of sound that reach the ears. This can be a major advantage to a person who has to deal with noise as well as light in an attempt to sleep.
If you work nights, for example, chances are your sleep is not as deep as it should be. After all, in the day there is just a lot more ambient noise around to keep you awake or to disturb your sleep patterns. On a flight too, the sound of the engines can be a bother to someone who is used to sleeping in a quiet room.
If you have a roommate or partner who has a different work schedule than yours, or is clumsy and noisy, sleep can be difficult to accomplish. If your partner or roomie snores, that can be a problem too. Some snorers saw wood loud enough to keep the whole block awake! Let alone the person trying to get to sleep right next to them! The attachment eye mask for sleeping can be great for those cases.
So, for many situations where you may not have much control over the amount of noise or light you are being assaulted by, a sleep mask is a good idea overall. Long car, train or plane rides, hospitals, night shift workers trying to sleep in the day, are just some situations where such an accessory might be useful. How much you need one, or how comfortable you would be wearing and using one, is something you have to decide.