What is the best memory data structure to hold a grid ? By grid i mean a rectangular table with rows and columns, where the entries are not single values, but can hold any information. Example: an availability "calendar", where i want to show room types as row headers (variable number), and dates as column headers (fixed, limited to 2 weeks at a time); and the intersaction being all information about the particular cell (e.g. booked, available, guest names, etc). Thanks for any pointers.