This article discusses how to use JavaScript to validate important types of form data, including names, addresses, URLs, email addresses, phone numbers, zip codes, expiration dates and credit card numbers (Visa, Master Card, Discover, and American Express, in both Canadian and US formats). By Joseph Myers. 1002
More here: How to Use JavaScript to Validate Form [...]

In this article, we look at how important JavaScript optimizations are analyzed. These general purpose techniques are designed for JavaScript on all browsers. Detailed graphs of all the performance results are given after each optimization. You will be amazed at the incredible speed improvements! By Joseph Myers
Originally posted here: Performance Optimizations for High Speed JavaScript

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