Chrome allows you to connect to the internet. It's fast, safe, and secure. And it's FREE!
It allows you to install programs, use peripherals (cameras, scanners, keyboards, etc), and work with files and data. It's fast, safe, and secure. Chromebooks are computers that run on the Google Chrome operating system.
The difference between the Chrome Browser and the Chrome OS are minimal.
Extensions are little programs that add useful functionality to the browser and to the websites you visit. Some extensions silently enhance your browsing experience while others have specific applications. Extensions can be installed from the Chrome Web Store.
Applications are programs that must be installed and run within the browser, performing a specific function. Some "applications" are little more than fancy links to a website. Others are sophisticated HTLM5 programs that look and feel much like a desktop application