Your Complete Guide to Microsoft Windows 10

Microsoft is rolling out Windows 10 beginning at 12 a.m. ET Wednesday morning. Here’s everything you need to know about the latest Windows operating system before installing it.

Microsoft’s personal digital assistant will feel familiar to anyone who regularly gives commands to Siri or Google Now, with one essential difference: Cortana will be baked into your desktop. As a result, Cortana can conduct a single search across your hard drive, as well as the cloud and the web, bundling the results into a single pop-up menu.

Ready to make the move to Windows 10? Here’s a quick and dirty guide to installing it. As with all major upgrades, remember to back up your machine first. It’s also a good idea to check if your computer can handle the new software.

When Microsoft’s Windows 10 launches Wednesday, a lucky few users will be greeted at the login screen by a cartoon eyeball that appears to want to lock eyes with its owner. Do so, and it will activate a 3-D face scan that signs in users in seconds, no password required. The Windows team calls this snappy new login feature “Hello.”

Windows 10 has a screen sensing feature called “Continuum,” which morphs your device’s layout according to how you’re using it. Got a touchscreen? Windows 10 strips away the tiny menus and fattens up the buttons. A PC? Back they go for easy clicking. The seamless switch from tablet to desktop suddenly makes those 2-in-1 tablet PCs — like Microsoft’s own Surface lineup — a far more enticing proposition.

Microsoft’s new Windows 10 software, out Wednesday, is effectively a sneak attack on Google, packing a new desktop search bar that can field just about any question under the sun. And it’s powered in part by Microsoft’s own Bing search engine, meaning the move could help Microsoft gain even more of the search market share against its foremost rival.

Microsoft’s effort to right those wrongs arrives this week with Wednesday’s launch of Windows 10 (the company skipped “Windows 9″). Windows 10 lets users easily restore the old Windows interface, while simultaneously gently nudging people to try the new style, too. I’ve been using a beta version of Windows 10 for some time, and it feels like a solid operating system. Over time, it will probably help Microsoft CEO Satya Nadella reach his goal of having 1 billion Windows-powered devices on the market by the next two-to-three years.

Microsoft’s Cortana team says the goal is to strike up a chatty, inoffensive rapport with users, in the hope that users will reward Cortana with their trust and open the kimono on their personal data. That data is critical to Cortana’s success, because if Microsoft wants to outwit the brainiest digital assistants on the market — Apple’s Siri and Google Now — Cortana will first need to take a good, hard look at your browser history, your emails and your web searches. With your permission, of course.

Microsoft has kept that dividing line in mind when designing the next generation of Office apps for Windows 10, which launches this summer. TIME got an early look at the new Windows Phone apps this week, which will be released in preview mode for Windows Phone Insiders by the end of the month. The company hopes the software’s new interfaces will let workers switch seamlessly from desktops to tablets to smartphones without straining their eyes, fingers or thumbs.

App developers whistled and applauded at Microsoft’s bombshell announcement Wednesday that they’ll be able to take code for Android and Apple apps and import it directly into the Windows ecosystem.

Microsoft announced last November Windows 10 would pack a technology called AllJoyn. An open source framework that encourages devices to be interoperable, AllJoyn was developed by the AllSeen Alliance, a group of more than 150 companies including the likes of Electrolux, Honeywell, LG, and Qualcomm that have banded together to make an open standard for Internet of Things (IoT) devices to speak to each other.

Microsoft has confirmed it will make Windows 10 available for purchase via a USB stick, replacing the iconic disc packages that have defined the brand’s image for decades.