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.

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。

1 TB at your fingertips. Protect your precious files, documents, and memories with OneDrive. You get 1 TB of cloud storage with a Microsoft 365 subscription, and can back up and share your files and photos with friends and family across all your devices.

Note: The steps to install the 2019, 2016, or 2013 versions of Office Professional Plus, Office Standard, or a stand-alone app such as Word or Project might be different if you got Microsoft 365 through one of the following: Microsoft Workplace Discount Program (formerly known as Home Use Program): If you bought Microsoft 365 for personal use through your company, see Install Office through ...

Keystroke. What it does. Windows logo key + R Opens the Run command. Windows logo key + S Opens Search. Windows logo key + E Opens File Explorer. Alt + Tab. Opens Task Switcher, moving forward with each press of Tab, switching to that window on release

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:

To pin apps to the taskbar. Select Start , select the arrow next to All apps, right-click the app, then select More > Pin to taskbar.

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.

Get help with signing in, changing passwords, creating and sending mail, deleting mail, creating folders, and more in Outlook on the web.

Try it! Universal search. Select Search on the taskbar or press Windows logo key + S, then type what you want to find.You'll get personalized search results for people, email, and files in local and shared sites, or from the web. Desktop groups