This is my mamma's recipe. We have it at most every family function.
Dice the bacon into small pieces and cook it in a frying pan until crisp. Set bacon aside on a paper towel to drain. Wash the broccoli and cut it into bite-sized florets. Mix the mayonnaise, vinegar and sugar. Place the broccoli, bacon and raisins in a large bowl and mix with the mayonnaise dressing until well coated. Refrigerate until ready to serve.
The bacon will get soggy if left to sit long, so add it right before serving if you plan on making it way ahead of serving time.