Most actually have an Alias to the the Applications folder which means simply dragging the app to the alias and the install is done. However FireFox’s image showing what to do is dumb. I remember the first time I downloaded FireFox and tried to drag the app to the image only to watch FireFox simply change position in the window. It was at this point I realised the idiocy of FireFox’s method.

I don’t think this was so much a switcher thing (I have several of those now), but more an “assumption about users” thing from the Mozilla gang. It was just unfortunate that Firefox happened to be the first application I installed.

Instead the files required by the application are stored within the application itself. Believe it or not a Mac app isn’t an exe in the sense of a Windows app but is actually a folder that contains the app. Double clicking effectively runs a shortcut that runs the executable in the folder but you don’t have to traverse the folder to run that executable.

Removing an app is a little trickier but is still easier than on Windows and more reliable if you have the right tools. I recommend App Delete which is a drag and drop uninstaller that works pretty well in most cases:

http://reggie.ashworth.googlepages.com/appdelete

The big problem for switchers is they continue to think about how Windows does things. A DMG file is more like an ISO so it needs to be mounted everytime you want to use it. I expect the image on the Dock you saw was because the DMG wasn’t mounted and so it had no idea where to look for the program.

A PKG file is more along the lines of the Windows Setup.exe and .MSI files but most applications don’t need anything more than a drag and drop but some require to copy files all over the place like for instance M$ Office which needs to place fonts in an accessible place and so they need the PKG setup.