The main difference is how you pay and update your software:

• Office 2021 is a one-time purchase. You get classic Office apps like Word, Excel, and PowerPoint, but updates are limited to security fixes.
• Microsoft 365 is a subscription service. It includes the latest Office apps, regular feature updates, and extra perks like 1TB of cloud storage. You can use it on multiple devices and always have the newest features.

Choosing between them depends on whether you prefer a one-time purchase or ongoing updates and cloud features.

It depends on the type of Office product you choose:

• One-time purchase versions (like Office 2021) are typically licensed for a single device. You’ll need a separate license for each computer.
• Subscription plans (like Microsoft 365 Personal) often let you install Office on multiple devices for one user. Always check the product details to see what’s included.

For families or multiple users, consider a plan that supports several devices to get the most flexibility.

To check if your computer is compatible with Windows 11, look for these key requirements:

• 64-bit processor with at least 1 GHz and 2 or more cores
• 4 GB RAM or more
• 64 GB storage or higher
• Trusted Platform Module (TPM) version 2.0
• Secure Boot capability

You can also use the PC Health Check tool from the official website to confirm compatibility. If you’re unsure, review your device’s specifications or consult with a tech expert before upgrading.

When you purchase an Office DVD or USB edition, you’ll typically receive:

• A physical disc or USB drive containing the Office installation files
• A product key for activation
• Instructions for setup and activation

This option is great if you prefer a physical backup or have limited internet access. Remember, updates and support may differ from subscription versions, so check the product details for specifics.

To help keep your Office software secure:

1. Enable automatic updates to get the latest security patches.
2. Use strong, unique passwords for your accounts.
3. Consider adding antivirus protection for extra safety.
4. Be cautious with email attachments and links to avoid phishing scams.

Staying up to date and practicing safe browsing habits can help protect your files and personal information.