There are hundreds of different piano chords, but actually you only need to know a few, especially if you want to play popular or rock on a keyboard. Here is a quick and easy way to know those chords without knowing ALL the notes.
Let's start with the most often used chord, C. C chord is the notes of C, E, G. You use 3 fingers to play these notes. With your left hand put the number 5 finger on the C. Without searching for the E or G note, just press down your number 3 finger and then your number 1 finger.
Let's go up to G. If you not sure where the G is, then read my article on reading notes or just alphabetically go from C to your right up the piano to G and stop. Also, the G is where your number 1 finger is when you play the C chord. Put your number 5 finger on the G, press down the G with number 5 and then press down your number 3 finger and your number 1 finger. You have make the G chord.
Let's do F. Find the F with your left number 5 finger and then press down the number 3 and the number 1. You have made a F chord.
You can do any chord by by using your number 5 finger as the guide. Put your number 5 finger on the note and press down your number 5 finger, number 3 finger and number 1 finger at the same time.
Note: Some of the chords will have a sharp in them which for this lesson will be the black key. When you press down your chord and it sounds "spooky" or "exotic" it is a minor chord. Fix it by simply putting your number 3 finger on the black key. You have instantly turned the minor chord into a major chord.
What is so nice about this, is you only need to know and find one note on the piano to play a chord.
Now your ready to try a rock progression. Play the C chord, then F chord, then G chord, then back down to the F chord. Repeat, C,F,G,F. Do this over and over again. Try variations like playing the C chord 6 times and the F chord 6 times, then the G chord 6 times. Play around and you can make your own rock songs with just these 3 chord variations.
Keep your hand in this position and use your number 5 finger as your guide to find the notes.