Once you use a sufficient number of software applications, you will notice something new – or at least if you don’t notice it yourself at first, it’s worth being aware of it – that many applications contain other mini-applications within them. The easiest way to understand this is to dig a bit deeper into the one of the most popular software applications out there – the browser.

Most of us use a browser to visit a “site” on the Internet. We don’t usually think about this but each site we visit, has its own unique set of requirements from the user/reader (you!) For example, if you watch a video on YouTube, you have to learn the specific ways in which a video can be stopped, started, paused, and so on.

In fact, knowing how to do that on YouTube, does not mean you will do it the same way on some other website that has videos – like, say, Netflix. The icons are different, and the features available are different. Netflix allows you to move back by 10 seconds while YouTube does not (at least as of when this blog post is being written.)

Each of these two ‘video players,’ then is another software application running inside the “main” application, which is your browser.

This is in fact a very common occurrence, and is part of how browsers are meant to be used – there is a way of describing the content inside the browser so that the browser knows you are going to interact with that content as if it’s an application independent of the browser itself. In later posts, we will start to see how that interaction works, and what programming languages are involved (spoiler alert – there’s a lot of JavaScript involved.)

But for now, we’ll focus on a different “application” that you can “run” inside your browser – Google Spreadsheet. All the behaviors that are available to you as part of Google Spreadsheet can be accessed from a browser – you go to spreadsheet.google.com, and the only requirement is that you have a Google account that you are logged in to.

Inside of this spreadsheet, we will find multiple programming tools and languages. It is not obvious at first glance, because you have to work it out in sequence, like a series of Russian Dolls encased in one another.