Good evening. This link
is a good read on cookies, but if you prefer the simpler version:
Cookies are text files placed on your system by various websites and although they can be easily removed, if you go back to the site(s) that put them there in the first place, they will put them there again and you'll have to remove them again. The only way to avoid a particular cookie is to avoid the site that puts it on your system.
Consider them to be the computing equivalent of the hangover and you have to decide whether they are sufficiently bad to stop you doing what causes them in the first place - obviously the hair of the dog doesn't work with cookies, or hangovers either in my opinion.
I hope this goes some way to answering your query.