Welcome to the wonderful yet complex world of computer animation! Through these pages I will try to show you everything old and new about the new animation system in Blender 2.4. But, before we get started, there are some basic notions about datablocks you should know. Animation in Blender is based on the fact that you have something moving in a Blender scene. For example, a ball bouncing on a floor plane:
-So you have a scene datablock, which holds some info about the scene itself, as you can see in the Render button window (F10KEY). -You populate this scene with various objects (which in this case refers to containers for data, not the actual mesh data that shapes the object itself). The only goal of an object is to hold the whereabouts of the data you want to see in your scene. It also holds the object instance's properties such as "does it have soft body or particle options, and do we draw its name?". Most of the info on an object can be seen in the Object Window (F7KEY).
An object links to all of the data you can see in a 3D view such as mesh, curves, nurbs, lattices, armatures, metadata, the empty property, text, camera and lamps.
So the ball you just added to the scene is in fact a mesh, linked to an object that is in turn linked to the current scene.
Now there are also data blocks you can't see in 3D view, such as material, texture, Ipo, action and image. Instead, you have a special window in which to edit them. This is the idea behind the Blender interface, wherein each data block has a window for you to edit the data.
So back to this bouncing ball: It's also moving across the plane! So an ""Ipo"" data block is linked to the object, telling it where in space the object will be at each frame of the animation. This Ipo is editable in the Ipo window when selecting the ball in 3D view. In Blender, the work you are performing is always on the currently active (selected) object and data.
Again, you are working in the scene "Scene", with an object "Sphere" linked to the mesh data block "Sphere" and the Ipo datablock "ObIpo". Why is that important? Because from there, you can start playing with the datablocks, linking them all around your projects to reuse old work. For example you can create more than one Ipo, and use the one you want, or tell more than one object to use the same Ipo, or to use the same object in more than one Scene.
Most of the linking job can be done in the Edit button window (F9KEY). Where you can tell an object to use another mesh's data block for Ipo, material, texture or image. There is always a little dropdown menu button for you to select an already-existing data block.
Now, when it comes to animation, you have to understand the way Blender handles data very well, because using Blender is always a matter of plugging data blocks together when working with Ipos, actions and NLA objects.