Two types of yarn overs are demonstrated here - a yarn over preceding a knit stitch and a yarn over preceding a purl stitch. Every knitter should have both in their knitting know-how!
by WoolyWondersCrochet
by Jayda InStitches
by Knitting Stitch Patterns
by ThePatterfamily
by Diba's Handicrafts
by Crochet Design
by Chodaros Bling