I'm definitely going to get some dirty-minded freaks out there responding to the title, but it still is important. A "ball band" is the paper that wraps around your ball, skein, or hank of yarn. Always keep the ball band - you will need it in your projects! 

Ball bands are invaluable for crocheters and knitters alike. Without it, your yarn is useless because you don't know how to care for it. And what a coincidence! I'm going to talk about how to wash and dry your projects too later. 

A ball band will contain this information:

1.) The weight of the yarn (ALWAYS LOOK AT THE BALL BAND BEFORE BUYING TO MAKE SURE YOU HAVE THE RIGHT WEIGHT). It will have a symbol like this, accompanied by its weight number:

2.) The composition (ex. acrylic, cotton, wool, lurex)

3.) How much is on the skein

4.) Washing and drying information

5.) Average gauge and needle/hook size

6.) Knitcheter's hack: often these have free patterns too! 

I cannot stress how important it is to keep the ball band with you, but I think I've made my point (oxymoron.) Let's talk about cleaning and care.

1.) Always handwash your pieces, even if the yarn says otherwise. It's risky to wash in the machine because the material could snag and fray, ruining your hard work. To handwash, fill a sink with cold water. Slip your piece in, submerging it, and put a dime's equivalent of detergent in with it. Let soak for an hour. Then drain the water and rinse out all the soap. Lay FLAT to dry.

2.) Never hang your pieces on a hanger or else they'll get distorted. 

3.) If your pieces smell bad (mine do this often), spray them down with Febreze. It'll kill the smell instantly and totally.

4.) Keep your gauge swatch handy in case you need to make a repair.

6.) If your yarn is still coarse after washing it, here's another crochet hack from your friend Joye. Submerge it in water again, but instead of leaving it, wash it like you would wash your hair: rinse it through with shampoo and conditioner. MAKE SURE IT'S RINSED OUT.

And that's all! Next will be patterns.