$_SESSION is a special array used to store information across the page requests a user makes during his visit to your website or web application. The most fundamental way to explain what a sessions is like is to imagine the following scenario: You are working with an application. You open it, make some changes, and then you close it.
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PHPMaster: PHP Sessions
Callum Hopkins is a designer and front-end developer with over 6 years web experience and has a Bachelors degree in Design for Digital Media. With knowledge in both design and development he is able to influence both sides of the web building process, and has a love for complex coding functions and beautiful design. Callum works as a developer for Deer Digital LTD and runs his own personal blog at callumeuanhopkins.co.uk where he writes thought provoking articles.