How often are newspapers and articles released?

I wanted to see if there were certain days newspapers are put on sale and why at those particular times. It would be easy to say when they are released, weekly, daily etc, but i wanted to know the reasons for this. It is different to news being reported online than it is on paper.

If a article is reported online, it can more or less be uploaded as soon as the story is found out and the article written. However for paper, the story would have to go out the next day, depending on when the story is heard of.

When it comes to a weekly newspaper, stories have to wait that long for them to be told in the paper, unless that newspaper has a website which is updated regularly.

                                        

After a lot of research i found that most newspapers in the UK are daily, and then have a Sunday version with a similar name, eg, Mil on Sunday (Daily Mail), Daily Star Sunday (Daily Star) and The Sunday Times (The Times).

This website has links to nearly every national and regional paper in the UK:

http://www.thebigproject.co.uk/news/