Web pages are becoming more and more complex, but browser vendors have been hard at work trying to offset that with performance and caching improvements. For example, Service Workers allow sites to cache certain data locally to speed up load times (or work offline entirely). 'Lazy loading' is another performance enhancement that has been in development, and now it has arrived in the Canary channel of Chrome.
The concept behind lazy loading is simple - images and frames that aren't visible to the user aren't loaded until they become visible. For example, if an article has an image halfway down the page, the image won't be loaded until the user scrolls down to it. Chrome developers claim that the feature improves initial loading times by 18-35%, depending on the page and internet connection.
The feature can be turned on by switching the Chrome flags #enable-lazy-image-loading and #enable-lazy-frame-loading to 'Enabled.' Lazy loading is applied to all images and frames by default, but developers will be able to override the feature with a new HTML attribute.