What are cookies and should you be using them?

A Cookie is a data file that is written on the user's computer by a program within a Web page. Cookies are often used to store information about:

• • Which pages a user has viewed
  • How many times a user has visited a Web site
  • What information the user has entered on past visits (e.g. login name and password or customer data)
  • What items a user has selected to purchase (shopping cart)
  
  
• A cookie stores information in pairs of variable names and associated values.  Each name/value pair is separated by a semicolon (;):
  userid=mkellog;password=hello;
• Information in cookies is essentially private.  Cookies can only be read by the same Web site domain name or IP address that created them.

Cookies are not necessary for many informational websites.  However, if you have subscription based content, are using a shopping cart or have a need to remember a user's identity from page to page.  Cookies are essential.  Generally, using cookies on a website requires a developer with some programming expereince in either JavaScript or in a server side language like PHP.

Labels: web programming, website tips