I use more than 1 browser tab when I surf online.
Is it possible to do that on the iPad or with a browser App?
Yes, as shady825 has stated below, Safari has tabbed browsing. I originally misread your OP.
Yes. Safari does have tabbed browsing.
It's not tabbed browsing.
You can have multiple windows, thumbnails of which can be viewed by tapping the button on the toolbar. Tabbed browsing is where all your pages are collected along the top of the window like the dividers of a folder. A single tap on a tab switches between windows.
That's not how Safari om the iPad
works.
^^^^ it's pretty much the same thing. Just takes up less screen real estate this way.
Really? Because you've been able to open multiple browser windows for years. Eventually they came out with "tabbed" browsing where you could keep multiple pages in the same window.
So no, they aren't pretty much the same thing.
So IMO, they are pretty much the same thing, except that Safari for iPad's method doesn't take up browsing window real estate.

Jesus! Who cares!?
All the OP wanted to know is he could have more than one tab/page going at once.
The answer is yes.
Although the refreshing of the pages kinda defeats the purpose I suppose.
Can the iPad in a similar fashion have several word / pages documents open at a time? Also, same question for powerpoint / keynote?
Can the iPad in a similar fashion have several word / pages documents open at a time? Also, same question for powerpoint / keynote?
Always find I have like 5 or 6 documents open at a time - would really be integral to me purchasing an iPad given my requirements / intentions with the device.
It all depends on the app that is being used. Only one app can be run at a time (with limited core exceptions, like music running in the background while you do something else) so having multiple documents open at the same time has to be done within an app itself. As an example, for pdf reading Goodreader (at the moment) only has one pdf open at a time, whereas iAnnotate can have multiple pdfs open, all tabbed within the app itself.
I think over time more and more apps will be developed that would allow more of a "multitasking" experience, though the iPad's OS is always going to be more restrictive than a true desktop experience.
In the fall the iPad is going to get the new OS which will allow some multitasking, but it still isn't going to be a full blown desktop type of multitasking, instead basically opening up what currently can be done by the Apple apps to 3rd party developers.