how to change column headers in a datagrid?

Question

I connected to a database and got all the data, but the headers of the columns have the namefields of the database, i.e. local_name, server_name....how do i modify the column headers in a datagrid, so that I could rename them into "Local Filename" "Server Filename"? One more question, how do I hide a column in a datagrid? Thanks a bunch! -aldrin