You really just have to get used to reading the reports.
Packed Powder - Soft ice. You can get a great edge in it. A lot of fun.
Hardpacked - Ice. You can get a good edge in it with sharp skis. Still fun, but takes some extra work.
Corduroy - Ice that formed after the groomers passed over it. It will rattle the fillings out of your teeth. Less fun, but you can still turn.
Golf balls - Ice that formed before the groomers passed over it. Skis will just slide around. There's nothing for them to bite into. Not much fun.
Powder - 1 inch (or less) of fresh snow on top of ice. Just enough snow cover that you aren't expecting that patch of ice underneath. Yuck. Why would you want that?
Mashed Potatoes - Ice that has warmed up under direct sunlight and become very wet and heavy. Tiring and great for hurting yourself.