In modern development, establishing a reliable and secure interface with which to authenticate your users is absolutely essential. OAuth 2 has pretty much emerged as the de facto standard here; however, because of its history, what exactly OAuth 2 means depends on who you ask (that is, if you ask Google, they may tell you a slightly different thing from Twitter).
In fact, should you wish to have someone simply log on with a secure interface, and you have little interest in the specifics of that login process, you could do a lot worse than using one of these companies to provide your identity services. For example, users could be able to log into your website with their Twitter credentials.
In this chapter, we will be developing a stock checking application. Our application will be very basic: we'll allow people to type in a...
