What is the lazy loading and how to best use it
In recent times we are often focusing on the issues of technical SEO and, in particular, it is increasingly necessary to have an informed approach to factors related to the performance of site pages, such as the loading speed or the Page Experience complex, which can become crucial to the success of our online project. Today we continue in this wake and we deepen the discussion on lazy loading, one of the most frequently recommended systems in particular to try to increase the speed of service of images: that’s what it is, how it works and how to avoid errors with slow or lazy loading.
What is the lazy loading
Simply put, lazy loading is a technique based on asynchronous resource loading and on downloading scripts on demand, that is only at the time when that portion of the page serves the user or when those resources are actually necessary for the continuation of the application.
In more technical terms, Google defines lazy loading (which can be translated into English as lazy or slow loading) as a UX best practice that involves deferring the loading of non-critical or non-visible content, which are loaded later than the main content.
Specifically, the expression refers to the process of loading elements of a Web page, such as images, videos, and scripts, only when they are about to enter the user’s viewport (the visible portion of the screen), so as to reduce the initial loading time of pages, improve the user experience, and limit resource consumption by the browser. This approach differs from traditional loading, where all elements on a page are loaded at the same time, regardless of their location or when they will be visible to the user.
What is lazy loading for
In theory, we can apply slow loading to all types of scripts, but in practice the lazy loading system finds more frequent use for images or videos: in any case, its ultimate aim is to lighten the weight of all the contents that can make slow the use of the page.
By only caring about the necessary elements, lazy loading reduces the initial page load time, allowing users to access content more quickly and providing a better user experience. Basically, we don’t have to wait for all the images and scripts on the page to load to start interacting with the content because thanks to the lazy instructions, the system automatically loads only the portion of the page that the user really needs at that moment, allowing it to streamline the download speed and optimize viewing time.
This strategy becomes essential to ensure a good use of the page to all users, regardless of the level of connection and the capacity of the network, and in particular to those who browse with mobile devices where loading is generally less fast than desktop devices (and in fact Google has cited lazy loading also talking about the best practices for the mobile-first indexing). In fact, lazy loading also reduces the consumption of resources (network and processing, such as CPU, GPU and memory) by the browser, providing a smoother browsing experience and limiting any connection or performance problems caused by slow connections or less powerful devices.
In this way, users do not suffer excessive slowdowns caused by connection problems and the overall weight of the overall content of the page, but they can view the necessary resources related to the part