Speaker 1: API, Application Programming Interface, a term that's way too long for what it does, which is just connect apps together. This is the only video you'll ever need about APIs after this, you're going to understand everything. I'll also give you some examples of how you can build cool apps using APIs, so let's get started. APIs just connect apps together, and you can think of an app as just some code running on a server. Now you can connect a bunch of small apps into one large app, like a puzzle, and the parts where they connect are APIs. For example, when you book an Uber trip, and this is the company I used to work for as a programmer, it might seem like one app to you, but there's actually hundreds of different apps running after you book that trip. One app is for your payment, one calculates your current location, and then one handles the review you leave at the end of the trip. And for each of these apps, there's probably a team of full-time software engineers in charge of it. Let's just take a look at the review app. To work, this app needs some data, who took the ride, who the driver was, and how many stars you left. This data is what plugs into the API. If the puzzle piece fits, aka the required data is received, then this app can do its job. We can also call the shape of this puzzle piece the API definition. Now it works in exactly the same way when you fill out a form on a website. There's required fields for username and password, and if you don't have both, then the form is not going to submit because the piece doesn't fit. These kinds of forms are part of the UI, or user interface, and notice the word interface is the same. So UIs work for the user, and APIs work for code. Now in the login form example, you have the UI, which connects to your front-end code, but to check your password, it also has to connect to your back-end through an API. In this case, the API has the same shape as the UI, expecting that username and the password field. So this data will pass through the UI, and then the API. So over here, this is our back-end, and we just connected to the login part of our API, but APIs usually have multiple pieces you can connect to. For example, the shape of login is user and password, but you can have a piece for forgot password that expects just an email, and you can have another piece for creating an account. Each of these pieces we can also call an endpoint. Okay, now pretty much every back-end has an API for its front-end, so it's not too much extra work to make this API accessible to the public. This makes the API usable by developers. So you're watching this video on YouTube through the user interface, and you might be aware that YouTube also has a public API. So right now you're getting the name, thumbnail, and file for this video through your user interface, but you could also get it through the API by writing some code. The thing is though, APIs like YouTube, they can't just make things 100% open, or people can abuse this. They can spam and basically overload a server until it shuts down. That's where the API key comes in. Think of it like a username and a password combined that uniquely identifies you. So if YouTube wanted to, they could see all the data you're requesting. They also set up rules around how many requests you can send per hour. I believe for YouTube it's around 200 an hour. For public APIs though, YouTube is just the beginning. There's APIs for pretty much everything. When you get into the Google Drive sheets and Gmail APIs, you can start to actually automate a lot of your job. For example, automating that really repetitive, boring work report by running a Google Drive script that does it for you. You can not only do that, but you can send it to your boss using the Gmail API. You can start to see that you can glue together multiple APIs with your custom code as the glue. You can use one action as a trigger for another. For example, you can connect a new post in a Facebook group to publish that to your Slack channel. Okay, so that all sounds pretty cool, but how exactly do you know how to use an API, or what shape the piece of the puzzle is? Well, that's where API docs or documentation comes into play. You kind of have to read up and understand the API, so there is overhead involved in starting to use each API. So connecting multiple together, getting API keys, reading the docs. Well, that probably sounds like a lot of work, and it kind of is. It does take time to set this up, but there's amazing tools like Zapier that allow you to connect APIs together with absolutely no code. And even if you can't write code, you can use a tool like Zapier to just do some amazing automation. So I really recommend checking it out. And it's absolutely free to get started and start playing around with a tool like that, and not sponsored, by the way. Anyway, that should give you a really good understanding of APIs. Just think of them as an interface for your code instead of an interface for the user. And if you have any interesting app ideas for connecting APIs together, let me know in a comment below. With that said, hope you learned something, and I'll catch you soon. Microsoft Mechanics www.microsoft.com www.microsoft.com