Um....just want to make sure I got this terminology correct. In 4/4 (to keep things simple), the down beats are the 1 (strongest beat) and the 3 (2nd strongest beat), and the back beats are the 3 and the 4 (weaker beats but the ones that are generally emphasized in rock). The "ands" (even-numbered eighth notes) are often called "off beats" but sometimes other weak beats are called off-beats also.

You typically use downstrokes on both the down and up beats (that doesn't help) and upstrokes on the off-beats.

Did I get any of this wrong?