When using Windows Explorer to view files, I'm given the option to set a "tag", "category", or other attributes. For a JPEG a different set of attributes (including "tag") are options. I'd like to be able to set these programmatically.
How do I programmatically set a file tag and other file attributes using Delphi (I have Delphi 2010 Pro)?
Tags in JPEG files are stored as IPTC keywords. There are a few libraries available for reading and writing those, if that's what you're asking for.
Explorer shows different columns for different file types because it knows that those file types support those extra columns. You can define shell plug-ins to support custom column information for your own file types. MSDN provides an overview.