General Information
Rats are long tailed nocturnal sociable rodents and they can make the most gentle, affectionate and intelligent pets. They are omnivorous with long incisor teeth continue to grow throughout life (but the cheek teeth do not).
The urine from a rat normally contains protein, which can sometimes lead to allergy in some people and is responsible for some of their odour that they give off! General cleanliness and regular cleaning of cages (and probably rats too!) can help stave this off, although I have heard that it is extremely difficult in unneutered male rats, who tend to be much more "smelly" than their female counterparts.
Rats as pets are relatively robust and male and female rats can be left housed together with their litters. They do need secure housing and sufficient space to make an interesting environment. They are great at playing with toys and need a stimulating environment around them, as they are very intelligent creatures. A variety of colours are now seen, the white albinos (which tend to have poor eyesight), self or solid colours (often brown or black). There are also mixed colours for example the "hooded" - white apart from a coloured head and shoulders and a stripe along the back.