I'm only going to include a few basic hints and tips for playing hard hands in blackjack, so that there will be something interesting to read in the sections on the specific hands.
The first thing you need to know is that you will always hit a hard 8 or less.
The next thing you need to know is that you will always stand on a hard 17 or better.
That only leaves strategy for eight more possibilities; all other possibilities are covered by the two strategies above. (And to make learning the strategy even easier, the same strategy applies to any total of 13, 14, 15, or 16, which reduces the total number of possibilities to 5.)
Hard 12's through hard 16's are called "stiff hands". These hands are always a bummer because they're often not good enough to beat the dealer's hand, but they also have a good chance of busting.
A hard 9 through a hard 11 is a potentially good hand for doubling down. See the individual strategy pages for each total to figure out exactly what to do with one of these totals and why.