JS High Set Note 1-2 Chapter

1,js is a scripting language made up of ECMAScript, Dom, and BOM designed to interact with Web pages. JS is one of the scripting languages.

2,mime, which is a type of file that sets an extension, is opened using an application, and when the extension file is accessed, the browser automatically opens with the specified application. Many are used to specify some client-customized file names, as well as some ways to open media files.

3, external files, placed in the head of the external file, will first explain JS after the body content, in the case of JS many times, in order not to let users wait and now generally will put JS into the body content finally . (P12)

Defer (deferred script): Runs the script after the entire page has been interpreted. (First-page script) (P13)

Async (Asynchronous script): download files now, but not in order, the current script does not have to wait for other scripts.

,<script> is executed sequentially when defer and async are not used .

JS High Set Note 1-2 Chapter