As with any pet, play and good company is all part of the fun. Rats are very sociable, and love human company. If handled from a young ages it will be second nature to them. It is advised to have more than one Rat, so they can keep each other company and develop to the fullest. It is widely known that most male Rats are more placid and are happy just to be cuddled, where as females tend to be more lively and in want to more play. Due to size females are easier to handle but are a bit more lively. Males are Bigger but have a "soppy" nature. I have always kept more male rats than females, due to their "soppy" nature, although females are just as loving. It is not advised to buy Rats from different litters and put them in the same cage, always buy 2+ males OR 2+ females from the same litter. I have never once had a Rat bite me, and i have kept a fair few Rats in the past 8 years. They will not bite if you give them no reason to, the occasional nip is quite normal, somtimes your hands may smell of somthing you were just cooking or handling, nipping is a way for Rats to test things. It is nothing to worry about and is quite normal. If your Rat is treated well, you will be rewarded with much love and companionship.