Ruby is the lowest grade of port. It is a blend of ports, wood-aged for a couple of years. It has a fruity flavour and a deep red colour.
Ruby is an inexpensive port. Practically speaking, it will do for most recipes that call for port, and is a good one to keep on hand. Find a ruby that you like to drink as well, so you can have the occasional snort.
Some Ruby Ports are aged for 4 to 6 years. They will be labelled LBV (late bottled vintage.)
The French prefer Ruby Port over other kinds.
After opening, store in the refrigerator (with the cork back in) anywhere for several weeks up to two or three months.