How can I maintain the count of how many persons have hit my site?

First of all we have to make one text file to store the no of value the user hit..At th first time the file count vatriable is 0 then every time when the form is load and user click on that form at that time we open the file and increment the counter variable by one then close the file in this way we can find that how many time the the page is hitted by the user.