A variable is used in PHP scripts to represent a value. As the name variable suggests, the value of a variable can change (or vary) throughout the program. Variables are one of the features that distinguish a programming language like PHP from markup languages such as HTML. Variables allow you write your code in a generic manner
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PHPMaster: Variables in PHP
Iain Tench has worked in the IT industry for 30 years as a programmer, project manager (Prince2 Practitioner), consultant, and teacher. As a project manager, he specialized in integration projects mainly involving payment systems in the financial sector. He now teaches and has acquired a Masters degree in Internet Systems Development as well as a teaching qualification. Iain's specialized areas of teaching is web technologies, mainly programming in a variety of languages, HTML, CSS and database integration. He's also written a book about Dreamweaver CS3 for Hodder Education.