table

hello,
I have a question about tables in Latex. I use tabular environment. I would like to have text in cell in my table in 2 lines.

For example:
--------------
| something |
| something |
--------------


now i have:

----------------------
|something something|
----------------------

i don't know which parameter i should use to change.
ps. which parameter in tabular is for column size?
i have such definition of my table
\begin{tabular}{||c|c|c||}

Hi Spider,

I think that this website has all the information your are looking for on LaTeX tables
such as controlling table width and height

hi,
i wrote
\begin{tabular}{||c p{2cm|c|r||}, but something is wrong. I don't know how use two parameter in one column for example "c p{2cm} "..... :(

I'm writing an exam where I want a table for the probabilities of a joint distribution. How can I do that in Latex?
I also want X and Y on the sides with the values that they assume.