{"id":143968,"date":"2025-01-09T14:19:27","date_gmt":"2025-01-09T08:49:27","guid":{"rendered":"https:\/\/data-flair.training\/blogs\/?p=143968"},"modified":"2025-01-09T14:19:27","modified_gmt":"2025-01-09T08:49:27","slug":"how-to-declare-variables-in-javascript","status":"publish","type":"post","link":"https:\/\/data-flair.training\/blogs\/how-to-declare-variables-in-javascript\/","title":{"rendered":"How to Declare Variables in JavaScript"},"content":{"rendered":"<h3>Program 1<\/h3>\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">\/\/ Declare a variable\r\n\/* \r\n     Dynamic Declartion (Auto)\r\n     var\r\n     let\r\n     const \r\n*\/\r\n\/\/ Dynamic Declartion (Auto) \r\n\/\/ a=10\r\n\/\/ console.log(typeof(a))\r\n\/\/ a=\"Hello\"\r\n\/\/ console.log(typeof(a))\r\n\/\/ a=true\r\n\/\/ console.log(typeof(a))\r\n\r\n\/\/ var\r\n\r\n\r\n\/\/    var a=100   \/\/global\r\n\/\/    console.log(\"Inside Type:\"+typeof(a))\r\n\/\/    console.log(\"Inside value :\"+a)\r\n\r\n\/\/ var a=\"Hello Friends\"  \/\/Redeclare\r\n\/\/ console.log(\"Outside Type :\"+typeof(a))\r\n\/\/ console.log(\"Outside  Value:\"+a)\r\n\r\n\r\n\/\/ Let\r\n\r\n\/\/     let a=100  \/\/ Local \r\n\/\/     console.log(\"Inside Type:\"+typeof(a))\r\n\/\/     console.log(\"Inside value :\"+a)\r\n\/\/    let a=\"Hello Friends\"  \/\/Redeclare\r\n\/\/    console.log(\"Outside Type :\"+typeof(a))\r\n\/\/    console.log(\"Outside  Value:\"+a)\r\n\r\n\/\/ var a=100  \/\/ variable\r\n\/\/ console.log(\"Type:\"+typeof(a))\r\n\/\/ console.log(\"Value :\"+a)\r\n\/\/ a=\"Hello\"\r\n\/\/ console.log(\"Type:\"+typeof(a))\r\n\/\/ console.log(\"Value :\"+a)\r\n\r\n\r\n\/\/ Constant\r\n  const PI=3.14\r\n\r\n console.log(\"Type:\"+typeof(PI))\r\n console.log(\"Value :\"+PI)\r\n\r\n PI=67.88\r\n\r\n console.log(\"Type:\"+typeof(PI))\r\n console.log(\"Value :\"+PI)\r\n<\/pre>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Program 1 \/\/ Declare a variable \/* Dynamic Declartion (Auto) var let const *\/ \/\/ Dynamic Declartion (Auto) \/\/ a=10 \/\/ console.log(typeof(a)) \/\/ a=&#8221;Hello&#8221; \/\/ console.log(typeof(a)) \/\/ a=true \/\/ console.log(typeof(a)) \/\/ var \/\/ var&#46;&#46;&#46;<\/p>\n","protected":false},"author":581,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[18979],"tags":[33503,33501,7758,31621,31622,33085,18982,33502,32082],"class_list":["post-143968","post","type-post","status-publish","format-standard","hentry","category-javascript","tag-declare-variables","tag-how-to-declare-variables-in-javascript","tag-javascript","tag-javascript-practical","tag-javascript-program","tag-javascript-program-on-variables","tag-javascript-variables","tag-variable-declaration","tag-variables-in-javascript"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.0 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>How to Declare Variables in JavaScript - DataFlair<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/data-flair.training\/blogs\/how-to-declare-variables-in-javascript\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"How to Declare Variables in JavaScript - DataFlair\" \/>\n<meta property=\"og:description\" content=\"Program 1 \/\/ Declare a variable \/* Dynamic Declartion (Auto) var let const *\/ \/\/ Dynamic Declartion (Auto) \/\/ a=10 \/\/ console.log(typeof(a)) \/\/ a=&quot;Hello&quot; 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