Oh I just found out it is 20 days.
10
The defalt setting is 20 days
In Internet Explorer, click on "Tools", then "Internet Options". You will get a drop down window with a section on "History" with the option of how many days to store the history, plus a button to "Clear History". Set the number of days to zero, then clear your history. This is also the drop down that lets you set your home page, clear cookies and delete internet files.
What is internet
Stuff
28 days
History is defined as a feature, which is used to access visited web sites. It maintains a record of all the sites visited in the current session or in the past few days or weeks depending upon the setup.
They were not, in the days of plantation ownership there was no "Internet".
greek roman days history of hospitality industry
Your best bet is to keep track of the days that you start and completely stop. If you want to find the average duration, keep track of the flow as well.
When I was a kid, I would have said an encyclopedia or a history book. These days, I would say you can get more and better information from the Internet (google.com).