Advance Measure

An advance measure is a technique used in web design and development to improve the perceived page load time for users. The primary purpose of an advance measure is to deliver content to users as quickly as possible, even before the user has fully requested it, thereby reducing the perceived delay between the user’s action and the page being fully loaded. This technique is especially useful for slower connections or when the server is under high load.

Purpose

The purpose of an advance measure is to improve the user experience by reducing the perceived delay when loading web pages. When users are browsing the web, they expect pages to load quickly and smoothly. However, if a page takes too long to load, users can become frustrated, leading to a negative experience. To prevent this, web developers use advance measures to make sure that the content is delivered to users as quickly as possible.

The use of advance measures can also help to improve the overall performance of a website. By reducing the amount of time that users have to wait for content to load, web developers can improve the perceived speed of their website, which can lead to increased engagement and improved conversion rates.

Usage

There are several different techniques that web developers can use to implement advance measures, depending on the specific needs of their website. Some of the most common techniques include:

Preloading

Preloading is a technique that involves loading resources before they are needed. This can include images, scripts, and other content that is required for the page to function correctly. By preloading these resources, web developers can ensure that they are available immediately when the user requests them, resulting in a faster page load time.

Preloading can be done in several different ways, including through the use of the link element in HTML, the rel attribute, and JavaScript. For example, the following code can be used to preload an image:

<link rel="preload" href="image.jpg" as="image">

This code tells the browser to preload the image.jpg file before it is needed, and to treat it as an image file.

Lazy Loading

Lazy loading is a technique that involves loading content only when it is needed. This can include images, videos, and other content that is not required for the initial page load. By delaying the loading of this content until it is needed, web developers can reduce the amount of content that needs to be loaded initially, resulting in a faster page load time.

Lazy loading can be implemented in several different ways, depending on the specific needs of the website. One common technique is to use the IntersectionObserver API, which allows developers to monitor when an element becomes visible in the viewport. When an element becomes visible, the content can be loaded dynamically using JavaScript.

Server-Side Rendering

Server-side rendering is a technique that involves rendering the HTML on the server before it is sent to the client. This can improve the perceived page load time by reducing the amount of work that the client has to do to render the page.

Server-side rendering can be especially useful for websites that have a lot of dynamic content, such as e-commerce sites or social media platforms. By rendering the HTML on the server, the website can deliver a fully-formed page to the client, reducing the amount of time that the client has to spend rendering the page.

Code Splitting

Code splitting is a technique that involves breaking up the JavaScript code into smaller pieces and loading them only when they are needed. This can help to reduce the amount of code that needs to be loaded initially, resulting in a faster page load time.

Code splitting can be implemented in several different ways, depending on the specific needs of the website. One common technique is to use dynamic imports, which allow developers to load modules on demand. For example, the following code can be used to load a module dynamically:

import("./module.js").then(module => {
  // do something with the module
});

This code tells the browser to load the module.js file dynamically, only when it is needed.