Windows 10 lets you view PDF files in the Edge browser, but it doesn't let you do anything with them. When you need to combine PDF files in Windows, you might wish you had a Mac because the macOS-only Preview app gets the job done quickly and easily. I make one exception to this rule: Adobe's free PDF-merge service. You may not want to give that metadata to a site you don’t know anything about, and that site could profit from your data in ways you won't like. Some of these sites seem to have no viable business plan, and their PDF-editing services give them the ability to harvest the data in your files, including invisible metadata, that can potentially identify you and your system.

With any operating system, you can always use an online app that combines and edits uploaded PDFs, but I’m leery about using almost all of them.

If you use Windows, you need third-party apps-good thing there are a few free, open-source options that do the job. Best Hosted Endpoint Protection and Security Software.

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