How to use Web 2.0 to make a database globally available?

I've just gotten a project in computer science, the task being."Investigate methods that could be used to make the database available to users outside of the Environ Now office building and describe at least two suitable methods."

EnviroNow being a fake company with a standard database at a set location that they want to be globally available (because everyone needs to know about their water sample issues [Love my teacher's sense of detail])

Now one of the options I've considered is using Web 2.0, however how does this actually work, is the database running from a set environment and people, over the web, alter it?

Also if you could suggest other methods, that'd be helpful too, however the main query is about using Web 2.0.

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