
Many Google Chrome / Android users often get confused with the difference between Google Play Store and Chrome Web Store. Google Apps and Chrome Apps often present a similarity, especially since most services supported on Google Apps are also featured in Chrome Apps. In this article, we will discuss about a few elements that make the definition clearer.
Chrome Web Store

The Chrome Web Store allows you to download and purchase apps, extensions and themes for your Google Chrome browser. Chrome Web Store is a web-based program or application that can work entirely on a browser.
Apps (Application)
Apps is a platform that you can run inside your browser with a dedicated user interface and, typically, rich user interaction. We’ve already had the concept of “web apps” in the browser for a few years, as something more rich and interactive than a website, but less cumbersome and monolithic than a desktop application.
An example of applications available in web store includes the game Plants vs. Zombies. The Store has been described as being like Google Play, but for "apps on the web". (From Wikipedia)
Extension
Extensions also provide functionality, but unlike apps, there is little or no UI component. Instead, they extend the functionality of Google Chrome and the websites being viewed in it.
For example, they can extend Google Chrome by adding a new button to the address bar, such as an ever-present currency converter. Buttons like this can also apply to the current website being viewed—for example, click the currency converter button to convert all prices on the website you’re viewing.
Google Play Store

The Google Play Store allows you to download and purchase Android apps, as well as music, movies, TV shows, e-books and magazines to your Android devices and accessories.
Google Play, was originally born and referred to by Google as the Android Market.
Google Play store is the official app store for the Android operating system, allowing users to browse and download applications and published through Google and has now allowed Chromebooks to use them. However, Google Play Store is only available on some selected Chromebook. Click here the list of selected Chromebook that support Google Play Store
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