Where\'s the Best Place to Put My JavaScript Files in an HTML Document?

Where to Situate JavaScript in an HTML Document

The placement of external JavaScript files in HTML is a crucial optimization consideration. The ideal location for scripts can influence the perceived performance of a web page.

Options for JavaScript Placement

The HTML document in question provides four possible locations for an external JavaScript file:

• In the Section: Before the CSS stylesheet link
• In the Section: After the CSS stylesheet link
• In the Section: Before the page content
• In the Section: After the page content

Recommendation:

According to the Yahoo! Exceptional Performance team, the recommended placement for scripts is at the bottom of the page, immediately before the closing tag. This is because browsers prioritize the loading of HTML components before JavaScript. By placing scripts at the end, the browser can render the page content while the JavaScript file is downloading in the background.

Conditional Placement:

The placement of scripts can also depend on the specific needs of the page. As mentioned by Levi, scripts should ideally be placed "just before you need it and no sooner." For example, if a particular JavaScript functionality is required immediately when the page loads, it may be appropriate to place the script in the section.

Conclusion:

The best placement for JavaScript in an HTML file depends on the specific context and requirements of the page. However, the general recommendation is to place external scripts at the bottom of the page unless there is a specific reason to do otherwise.

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