i want make javascript application that's not open source, , wish learn how can obfuscate js code? possible? obfuscation: try yui compressor . it's popular tool, built, enhanced , maintained yahoo ui team. you may use: google closure compiler uglifyjs private string data: keeping string values private different concern, , obfuscation won't of benefit. of course, packaging source garbled, minified mess, have light version of security through obscurity . of time, it's user viewing source, , string values on client intended use, sort of private string value isn't necessary. if had value never wanted user see, have couple of options. first, kind of encryption, decrypted @ page load. 1 of secure options, lot of work may unnecessary. base64 encode string values, , easier.. wanted string values easily decode them . encryption way prevent accessing data, , people find more security need. sidenote: obfuscation in javascript has been kn...