JScript

JScript is Microsoft's <a href="/facts/Legacy_software/YvYjMcCz">legacy</a> dialect of the <a href="/facts/ECMAScript/M7nDHsB5">ECMAScript</a> standard that is used in <a href="/facts/Microsoft/nGIDDXdx">Microsoft</a>'s <a href="/facts/Internet_Explorer/uL8a4Y5l">Internet Explorer</a> web browser and <a href="/facts/HTML_Application/mkk6xJSk">HTML Applications</a>, and as a standalone Windows scripting language.
JScript is implemented as an <a href="/facts/Active_Scripting/0v27X50A">Active Scripting</a> engine. This means that it can be "plugged in" to <a href="/facts/OLE_Automation/9Nqpxz4z">OLE Automation</a> applications that support Active Scripting, such as <a href="/facts/Internet_Explorer/uL8a4Y5l">Internet Explorer</a>, <a href="/facts/Active_Server_Pages/um62st21">Active Server Pages</a>, and <a href="/facts/Windows_Script_Host/xJ0qFfo9">Windows Script Host</a>. It also means such applications can use multiple Active Scripting languages, e.g., JScript, <a href="/facts/VBScript/tg6VhSCk">VBScript</a> or <a href="/facts/PerlScript/uydYqvDj">PerlScript</a>.
JScript was first supported in the <a href="/facts/Internet_Explorer/uL8a4Y5l">Internet Explorer 3.0</a> browser released in August 1996. Its most recent version is JScript 9.0, included in Internet Explorer 9.
JScript 10.0 is a separate dialect, also known as <a href="/facts/JScript_.NET/BvBS09IC">JScript .NET</a>, which adds several new features from the abandoned fourth edition of the ECMAScript standard. It must be compiled for <a href="/facts/.NET_Framework/J6QDAUhP">.NET Framework</a> version 2 or version 4, but static type annotations are optional.
JScript has been criticized for being insecure and having multiple security bugs "exploited by nation-state actors", leading Microsoft to add an option to disable it.

JScript open-in-new

JScript