At what point does someone cross the line from being computer-illiterate to computer-literate? I don't think it's about qualifications, or training courses or having used n different programs. It's more to do with attitude. People who are computer illiterate admit as much. They write down a list of instructions which they follow every time they (for example) write an email. If they realise they've missed out a step, they won't know what to do. They won't attempt anything new without being shown.
Computer literate people may not be able to do much, but they get better. They may have an idea that they want to do something, and try things out on the menus and toolbars until they get close enough. They start to understand concepts, and apply them to different programs.
The problem when writing software is catering for both groups.