What they are
Support = a price level where buyers have historically stepped in. Resistance = where sellers have historically taken control. The more times a level is tested, the more it matters — until it breaks.
Draw zones, not lines
Markets are messy. Draw levels as thin zones (a few points wide), not razor-thin lines. Price rarely hits the exact tick.
Broken support becomes resistance
When a support level breaks and price retests it from below, that old support often acts as new resistance. Same logic in reverse.