[vtkusers] 3d data format??

[Manan Syal]

hello all...
i am new to VTK. I am trying to render some 3d data... i have
uncompressed data, which i need to render in the form of meshes..i have
gone through the examples, and realize that the user must specify data
at each point, and the connectivity list between the points..
is there any example or any other link where i can find the (user )data
structure required by VTK to render volumes ?
please reply at the earliest..need help with this one..
manan