The base Android screenshot shortcut is the same on every brand: hold Power and Volume Down. Where things differ is the bonus methods (scrolling captures, S Pen, palm-swipe, three-finger swipe) and where the file ends up afterward (Photos vs Gallery). Once you know the variants, you'll never need a third-party screenshot app on Android again.
Power and volume down, and what to do when nothing happens
Press both buttons at the same moment and release. Holding them a beat too long brings up the power menu instead, which is the single most common reason people think their phone cannot do it. If you get the power menu, you pressed volume down late.
A phone with a case that sits proud of the volume rocker makes the timing harder, because one button registers before the other. Take the case off and try once to rule it out. On a Samsung with Bixby remapped to the side key, the same press can trigger Bixby instead, and that setting lives under Advanced features.
Scrolling screenshots for a whole page
A normal capture stops at the bottom of the screen. For a full web page, a long chat or a receipt that runs past the fold, take the screenshot as usual and then look at the toolbar that appears at the bottom. Tap Capture more, or Scroll capture on a Samsung, and keep tapping while the page scrolls itself. Each tap extends the image.
The result is one tall image, and the crop tool that opens straight after is how you trim off the part you did not want. Not every app allows this: the button is missing in apps that do not report a scrollable view, which is most video and camera screens.
Gesture shortcuts, which vary by brand
Samsung has palm swipe: drag the edge of your hand across the screen from one side to the other. It lives in Settings, Advanced features, Motions and gestures, and it is off by default on some models.
Xiaomi, OnePlus, Oppo and Realme use a three finger swipe down. Motorola uses a three finger touch and hold. Pixel has no gesture at all, but it does offer a screenshot button in the recent apps view, which is easier one-handed than the button combination.
Google Assistant will also do it if you ask out loud, on any brand, which is the only method that works when one of your hands is full.
Where the file goes
On a Pixel or a stock Android phone the file lands in Google Photos under Library, then Screenshots. On a Samsung it goes to the Gallery app in an album of the same name. Either way the file itself sits in the Pictures/Screenshots folder on internal storage, which is what you browse to if you are pulling it off over a cable.
Screenshots save as PNG on most phones, which keeps text sharp and makes the files bigger than a photo of the same size. A few hundred of them will quietly fill a backup allowance, so it is worth clearing the album out now and then. The Photos app can filter to Screenshots and delete the lot in one pass.
When the app refuses
Banking apps, most streaming apps and anything in incognito mode block screenshots at the system level and hand you a blank image or a toast saying the app does not allow it. That is deliberate and there is no setting to turn it off. Photographing the screen with another phone is the honest workaround.