You are interested in using "cookies" and "user authentication". Both of these are rich and complex topics. I suggest you use those as keywords to Super Search
here on PM, or on google, and also check out some of merlyn
's writings, such as Basic Cookie Management
to help you get some background information and techniques.
There are quick answers to your questions, but getting a good grip on the big picture is priceless.
Are you posting in the right place? Check out Where do I post X? to know for sure.
Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
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<blockquote> <br /> <dd>
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<code> tags not
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tags should generally be avoided. If they must
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horizontal scrolling (and possible janitor
Want more info? How to link or
or How to display code and escape characters
are good places to start.