“Offline Web Applications” is the new buzzword these days. The apps that used to work only when you are connected to the Internet are being redesigned so that they can be used offline. In HTML5, this is made possible through an application called cache manifest. Even without a network connection, you can access a web-based application as if you are still connected to the Internet.
What is Cache Manifest?
Web applications these days are composed of web pages that have to be downloaded from a network. This means that in order to load the page of a particular web-based application, connection to the Internet is required. If the connection is unstable, or if there is no network available, this becomes a problem to the user. With cache manifest, users can do offline browsing without experiencing slow webpage loading problems. This is because cache manifest specifies which files should the browser “cache” and make available to offline users. (As you all know, cache is a computer term that pertains to the capability of computers to hold copies of data that were recently accessed, like a picture on web pages. You can access them easily because instead of going to the original web page, the cache gives you the latest copy of the photo which was stored on your desktop.) A cache manifest is a text file that developers use to store the resources that they want to load from their local storage instead of the server. Simply put, the manifest contains a list of resources that a particular web application can access when there is no network connectivity or while the gadget is disconnected from the network. Developers can define the web pages that can be cached and those that cannot. They can also define the page that should be shown to a user in case they access an un-cached page. The manifest file only has to be included on the web page that apps developers want to be cached. If you are a developer, you need to point to the manifest file in order for the process to work.
How Cache Manifest Benefits Offline Web Applications
Some applications rely heavily on services and data from the Internet and their functionality is reduced when the user experiences unstable Internet connection. If the application is offline capable, users get enhanced experience when using a particular app, and this can eventually translate to increased app usage. There is speedy access to the application even if offline because, as you know by now, everything relied on cache. Moreover, since the browser only downloads those resources that have been changed from the server, server load is reduced, thus lessening chances of network overload. Internet connections are not always reliable but that should not prevent you from making your apps reliable even while offline. With cache manifest, you can differentiate your site from your competitors and this will create a larger opportunity for you.