First, let me just get this out of the way. iPad won't be able to project like your laptop. With a laptop you just plug in the cable and everything is projected onto the screen. iPad does not work like this unfortunately.
To be able to hook your iPad into a projector you will need a "dongle" from the Apple Store. (The official name is Apple iPad Dock Connector to VGA Adapter). This dongle will set you back $29.00 and is available in Apple Stores.
Unfortunately you cannot just plug in the cable and project everything that happens on your iPad screen. Projecting from the iPad is app dependent. Certain apps support projecting but most of them don't. So before purchasing any apps you want to use for projecting make sure you do some research if the app is capable of doing it. **HINT- while browsing the App Store in iTunes or on your iPad, each app that is capable of being projected will state this in their app description.
Here's a few iPad apps that support projecting.
-Keynote. Projects your presentations (PowerPoints, Keynotes, among others). You can use your finger as laser pointer. Just touch your iPad screen while you project your presentation.
-GoodReader. Projects your documents (Word, PDF, etc).
-YouTube. All the video clips you can find on Youtube can be projected.
-Videos. All the videos you have on your iPad can be projected.
-Photos. All the photos you have on your iPad. You have to turn slideshow on and projecting will start.
-WebShow + VGA Out. This app is just like the Safari browser but it is capable of projecting the browser window.
-PaperDesk. Able to project your notes (typed or drawn).
Here's great guide how to get your PowerPoints into Keynote app.