Adobe Acrobat Reader (Free)

Adobe Acrobat Reader is the standard for viewing PDF documents. While it is reliable for opening and reading files, the free version is heavily focused on pushing users toward Adobe's paid subscription services. The interface is often cluttered with ads for premium features like PDF editing and conversion.

It is a heavy, resource-intensive application for a task that most modern web browsers can handle just as well. Unless you specifically need advanced PDF features, the free reader is often more trouble than it is worth.