It's basically the same Nintendo Switch you're used to, with a few caveats.
Why it matters: Worried you're going to have to get used to some new, weird version of the Switch with a different menu interface or other changes you're not so keen on? Don't worry -- not a lot is actually changing from one model to the other.
The Nintendo Switch Lite will still offer most of the same features you've come to expect from the system, but sized down considerably to a cute, handheld size that ends up shaving off about half-an-inch of screen space versus the original. For one thing, it will still support amiibo by way of near-field communication (NFC), wireless play, and Bluetooth connectivity. It's made to be portable, so everything that helps make it be just that is still included.
It also comes in some particularly adorable colors: yellow, blue, and gray, which are interesting pastels that Nintendo hasn't really experimented with in the past. There's also an attractive Pokémon Sword and Shield version that features cyan and magenta face buttons with Legendary Pokémon emblazoned across the back of the unit that will be available in November. No more boring black units for you, or having to match Joy-Cons to each other for a decent color combination.
There are some drawbacks, though. Since you can't detach the Joy-Con or use a kickstand, some games and game modes are off-limits, like the multiplayer game 1-2-Switch. You won't have the HD Rumble necessary to communicate useful information in that particular title, but as far as the list of incompatible games goes, it's pretty short.
Unfortunately, that also means you can't use it with the fun, cardboard-centric building kits that come with the Nintendo Labo software sets. These often require you to detach the Joy-Con controllers to use the screen/Switch base unit to drop into cardboard goggles or "toys" that can be used with everyday objects like rubber bands or reflective tape. Since you can't remove the controllers, you won't be able to do this. It's a bummer, for sure, especially if you enjoy DIY gaming projects.
Part of the trade-off is better battery life, though, which should offset some of the drawbacks that come with being unable to play certain games. You'll get anywhere from 3 to 7 hours of battery life, depending on which games you play, which is longer than the traditional Switch's 2.5 to 6.5 hours. It's still nothing like the lengthy battery life of the Nintendo 3DS, but it's definitely getting there.
The bottom line: You get the tried-and-true Switch functionality with funky colors, better portability, and better battery life at a lower price, even if there are some titles you can't play.