Unlike earlier load optimization techniques, such as prefetching, lazy loading does not pre-load resources until it is absolutely necessary. Instead, it waits until the user requests a specific resource, such as an image, before downloading it from the server. This helps reduce the amount of data that is transmitted across the network, as well as the time spent waiting for the item to load.
The idea of lazy loading has been around for some time, but it has become particularly noteworthy with the advent of JavaScript-driven websites. With these types of sites, it is now possible to dynamically load assets depending on the context of the page. For example, if a user is not going to view an image, the image won't be loaded, resulting in an overall faster loading time and quicker page rendering.
On top of this, lazy loading also reduces the amount of code that is sent to the browser, making the webpages lighter and easier to render. Because of this, pages with images become much faster after the lazy loading of assets. This type of optimization technique is especially beneficial to users with slower connections, as it allows them to save their bandwidth and receive faster page loading times.
In addition, lazy loading improves page performance by reducing the amount of memory that is taken up by the page. This frees up more memory on the device so that other webpages can be rendered faster and more efficiently.
Finally, lazy loading helps reduce the amount of work that a website must do when loading pages—a process that is particularly important for larger websites. With this technique, a website can save resources and achieve greater performance.
In conclusion, lazy loading can be an extremely effective technique for improving a website's performance. By reducing the amount of data that is transferred across the network, speeding up the loading of content, and freeing up memory on the user’s device, optimization through lazy loading can lead to faster page loading times and improved user experience. Furthermore, by reducing the amount of work that a website has to do, websites can become more efficient. As such, lazy loading should be considered as one of the primary optimization techniques to consider when looking to improve a website's performance.