SC is the abbreviation for single crochet stitch.
Single crochet is one of the most basic crochet stitches. It can be used alone or in combination with other stitches. SC can be worked in either rows or rounds.
How to Work SC Stitch:
SC is also an abbreviation for the state of South Carolina. If you need information about South Carolina, visit the South Carolina travel guide.
Ch 20, sc in second ch from hook.
This Translates to: Chain 20, then work a single crochet stitch in the second chain from your crochet hook.
When speaking with other crocheters, I would advise you to say the entire phrase "single crochet" rather than trying to pronounce the abbreviation "sc." I've never heard a crocheter use the sounds for sc instead of saying the entire phrase. The abbreviation sc is typically used as a convenient way to save space in printed patterns, and isn't meant to be used in conversation.