Partially stolen from this answer (and here's third party confirmation):

Hold the Back button and tap the Home button (or, if that doesn't work, tap both at the same time). This is part of Samsung's TouchWiz interface, it doesn't work on other devices.

On most other devices, the only way to take a screenshot without rooting is to use the Android SDK. You would connect your phone to your PC via USB, run ddms, select your phone, and hit Ctrl+S.

Partially stolen from this answer (and here's third party confirmation):

Hold the Back button and tap the Home button (or, if that doesn't work, tap both at the same time). This is part of Samsung's TouchWiz interface, it doesn't work on other devices.

On most other devices, the only way to take a screenshot without rooting is to use the Android SDK. You would connect your phone to your PC via USB, run ddms, select your phone, and hit Ctrl+S.

Partially stolen from this answer:

Hold the Back button and tap the Home button. This is part of Samsung's TouchWiz interface, it doesn't work on other devices.

On most other devices, the only way to take a screenshot without rooting is to use the Android SDK. You would connect your phone to your PC via USB, run ddms, select your phone, and hit Ctrl+S.

Partially stolen from this answer (and here's third party confirmation):

Hold the Back button and tap the Home button (or, if that doesn't work, tap both at the same time). This is part of Samsung's TouchWiz interface, it doesn't work on other devices.

On most other devices, the only way to take a screenshot without rooting is to use the Android SDK. You would connect your phone to your PC via USB, run ddms, select your phone, and hit Ctrl+S.