Mattress 101 is a regular series that covers the ins and outs of mattresses and their components. From memory foam and innerspring mattresses to hybrids and more—we’re covering what they’re made of, how they’re used and how they can help you get better sleep.

When you think of mattresses, you probably gravitate to foam. And for good reason! It’s what almost half of the beds in the world are made of. We’re here to help you understand the types, perks and benefits of foam in a mattress. We’ll even uncover (ha!) some science and history along the way. So, get your mental notebook ready, because we’re breaking it down.

The Definition of Foam

Ready for some science to put you to sleep? Don’t worry—we’ll keep it short. In terms of the science of foam, it has a slightly different meaning, depending on the state of matter you’re talking about (hello, 7^th grade science class!). It can be either a liquid or solid, and is created by trapping tiny air bubbles within an object—either liquid or solid. So if you think about the foam in your mattress, it truly is a solid object that traps tiny pockets of air in it. Think of it like a sponge, but way more comfy.

The Uses of Foam

You might be thinking, “So, you just sleep on a big chunk of foam like it’s a floatation device, or what?” And, if it were 1990, you wouldn’t be too wrong. But today, foams and their functions can be broken down into three categories.

• The comfort layer is usually found at the top of the mattress and is designed solely to adapt and contour to your body. Nowadays, this layer is usually the most flashy in that they sometimes provide breathability and even cooling! Cool, huh?
• The core support layerisn’t one that gets talked about enough, but without it, your mattress would sag and collapse into a deflated pile of foam. It is usually a thick layer of compacted foam that serves as the backbone of your bed.
• The edge support layer of foam is another one that flies under the radar, but is vital to your sleep. It’s another layer of foam, usually compacted foam, around the outside of the bed, that keeps the walls of your bed in place, so you don’t roll off when you’re in the middle of an intense dream.

Different Types of Foam

When it comes to foam types in mattresses, there are really three you should know. While we love them all, what kind of sleeper you are (back, stomach, side, handstand, etc.) will determine which is your best fit.

• Polyurethane foam. Yes, this layer may take you four attempts to spell while writing this blog, but it’s okay. Because this type of foam is kind of the unsung hero of foams. One of the most common foams in beds, it serves as the core support in all foam beds and is usually highly compacted to give your bed the support it needs night in and night out.
• Memory foam. You have heard of this one, for sure. Also called viscoelastic foam (memory foam is so much cooler to say), it’s similar to polyurethane foam in that it’s highly compressed, but the difference comes in the engineering after you’ve lied on it. Instead of simply compressing under pressure, it’s designed to let up and soften up after pressure is applied, which means a mattress that’ll hug you right back as you sleep. Memory foam makes your sleep unforgettable (maybe that’s why they call it that).
• Gel-infused foam. This is arguably the most techy of the foams. It’s one of the aforementioned foams, but it’s infused with something else to keep you cool as you sleep (usually gel liquids, gel pads or gel beads). No matter what goes into it, a cooler, more breathable sleep comes out of it.

Why is foam right for me?

We’re not here to disparage one type of mattress over the next, but there’s something about foam that makes us want to nap. The main difference you’ll notice is that foams instantly adapt to your weight without providing a hint of tension to push back against your body (some coil-only mattresses do the opposite). This creates an astoundingly different feel and provides a pressure-relieving, body-conforming snooze. But wait—there’s more!

• Foams provide enhanced pressure relief by not pushing back against the body, eliminating the number of pressure points and helps to alleviate the associated pain.
• The various comfort foams, especially memory foams, absorb and isolate motion rather than send it to your partner, eliminating disturbances as you sleep.
• High-quality foams provide advanced support to the sleeper by contouring themselves to the curves of the body, allowing the sleeper’s spine to remain in a neutral position. AKA it’s got your back.

Now, it’s time to get comfy. If all this learning made you want to take a nap, we’re right there with you. Whether you’re searching for your dream mattress or just want to learn a thing or two about beds, you may want to test a few beds out in person to see the difference. You’ll never forget how comfy a memory-foam mattress is. Maybe that’s why they call it that.