But other creatures which appear on Halloween crafts and Halloween party decorations really do exist. There is nothing made-up about cats, bats and spiders - and some of the superstitions and patterns of behaviour associated with them really are a little spine-chilling.
No Halloween witch is really alone if she has a black cat as a companion - preferably a skinny one with sharp teeth, a tail pointing up to the sky and eyes which glow in the dark.
In the Middle Ages some very superstitious people believed that all people who had black cats were witches. This resulted in a reluctance to own black cats as witches were persecuted and often killed.
A more enlightened attitude to black cats emerged as plagues swept Europe and people realised that the more cats there were the less disease-carrying rats there would be.
But superstitions about black cats still exist today. A black cat crossing your path can be seen as a sign that you will suffer bad luck; especially if they cross your path from left to right.
Some superstitions about black cats are so silly that they have almost completely died out. The idea that a black cat which walks towards you is the bringer of bad luck and one which walks away is the bringer of good luck can have made little sense even in the 19th century - if this was the case, who would ever want to own a black cat?
Luckily, folk of today have a more enlightened view of black cats. Many people in Great Britain now see black cats as lucky creatures. And in Japan, a lady who owns a black cat is thought to be destined to have many male admirers - unlike witches!
Surely bats which feed on blood, like Count Dracula in horror films, don't exist?
Well, strange though it may seem, they do.
In the humid and tropical caves and forests of Central and South America there are three species of vampire bats. One of these species is called the hairy-legged vampire bat; a funny name for an animal which sucks blood from its prey.
According to a recent scientific research, vampire bats can locate blood `hotspots' on their prey by using infrared vision.
And they have another useful skill as - unlike other bats - they can run on land; an ability which shocks and surprises many of the creatures they feed off.
These bats aren't all bad; they are the only members of the species which will adopt another bat if a fellow member of the colony becomes orphaned.
The common vampire bat is not so kind towards humans; it will (and does) quite happily sink its teeth into any sleeping mammal to get the blood it needs to survive!
Black Widow Spiders
Spiders are seen on many Halloween decorations - probably because many of us find these creatures so scary and spooky. Most spiders are absolutely harmless but this isn't the case with the Black Widow Spider.
This web-weaving creepy crawly gets its name from the fact that the female very occasionally kills and eats males after mating with them (clever lass!). They definitely contain a more poisonous bite than the males of the Black Widow species - a reason why the males only go near a female's web during the mating season.
Insects which stumble into a Black Widows' web risk being immersed in silk produced by the spiders' back legs. The silk immobilises the prey and gives the spider plenty of time to administer a fatal poisonous bite.
Luckily, Black Widows live far south of Britain in places like America, Africa and Australia.
Although their bite is 15 times more dangerous than a rattlesnake's they normally only plunge their teeth into humans if they feel threatened.
So, in the highly unlikely event of one appearing near your bath plug this Halloween, don't panic!