但如果需要测试多个条件，例如我们假设所有条件都需要为 True 或 False (AND)，或只有一个条件需要为 True 或 False (OR)，或者如果想要检查某个条件是否不 (NOT) 符合你的条件，这时该怎么做呢？这三个函数均可以单独使用，但它们更常见于与 IF 函数成对使用。

Set backgrounds for desktops. You can also choose different backgrounds for each desktop if you're using a picture. If you're using a solid color or a slideshow, all your backgrounds will be the same.

On a Mac? See Check for Office for Mac updates automatically.. Click here for the Latest updates for versions of Office that use Windows Installer (MSI).. Choose your version of Office. If you're not sure what version of Office you have, see What version of Office am I using?. Not sure which type of install you have?

Save to a file - You can save your recovery key as a plain text file on any device. If you need that file in the future just open it with any text editor like Notepad or Microsoft Word and you'll be able to read the key.

Windows Security provides built-in security options to help protect your device from malicious software attacks. To access the features described below, tap the Windows Start button, type windows security, select it from the results, and then select Device security.

The new Microsoft Edge is based on Chromium and was released on January 15, 2020. It is compatible with all supported versions of Windows, and macOS. With speed, performance, best in class compatibility for websites and extensions, and built-in privacy and security features, it's the only browser you'll ever need.

USB-C overview. With a USB-C connection, you can charge your Windows 11 PC, and you can also connect to other USB Type-C devices such as mobile phones, docking stations, display adapters, and other devices that have a USB-C port.

To access your sign-in options, go to Start > Settings > Accounts > Sign-in options.. Or just select this button: Go to Sign-in options. Change or manage your password or PIN. To change your password or PIN, go to Start > Settings > Accounts > Sign-in options. Select PIN (Windows Hello), and then select Change PIN.

Cookies are small pieces of data stored on your device by websites you visit. They serve various purposes, such as remembering login credentials, site preferences, and tracking user behavior.

Updates to the default screen and sleep settings now help you use energy more efficiently and extend battery life. You can find efficiency settings in Windows 11 at Settings > System > Power & battery.. For a guided walkthrough of how each of the power and battery settings can improve your device's performance, click the button to open the Get Help app: