@Kolyo,
if at all possible keep your cat(s) inside only. Too many things can happen to them outside from fights to being run over, poisoning, loose dogs or other animals killing them, diseases.
If you have a situation when the cat is so miserable inside that it makes you miserable keeping it in and you are on a very traffic free quiet street or in the country it might be safer.
I've heard outside cats live an average of 4 years. People can set up or have an area set up outside that is enclosed somthe cats are safe but enjoy the outside.
One f my cats has always been inside only. The other was a somewhat feral stray cat I had soayed, got her shots and tried to keep inside but screamed non-stomto go out and she is now i side outside-in after dark.
Halloween make sure your cats especially black cats in for a good week before Halloween. There are some sick people out there.