From http://www.andy-roberts.net/writing/latex/tables
The tabular is another such environment, designed for formatting your data into nicely arranged tables. Arguments are required after the environment declaration to describe the alignment of each column. The number of columns does not need to be specified as it is inferred by looking at the number of arguments provided. It is also possible to add vertical lines between the columns here. The following symbols are available to describe the table columns: l left-justified column c centered column r right-justified column p{width} paragraph column with text vertically aligned at the top m{width} paragraph column with text vertically aligned in the middle b{width} paragraph column with text vertically aligned at the bottom | vertical line || double vertical line Once in the environment, & column separator \\ start new row \hline horizontal line to adjust the spacing between rows in a latex table, add square brackets and the size adjustment after the linebreak. for instance, to compress rows by 1 inch: entry1 & entry2 & entry3 \\[-1in]