Connect a JavaScript app to Microsoft 365
You can increase the value of your web apps by connecting them to Microsoft 365. Microsoft 365 contains data and insights that people create in their workplace every day in the form of emails, files, and chats. By showing this information in the context of your app, people can easily access the necessary information without having to leave your app. By combining your unique functionality with organizational information from Microsoft 365, your app can offer more value.
Authenticate to access data from Microsoft 365
You connect your app to Microsoft 365 through Microsoft Graph, which is the API that exposes data and insights stored in Microsoft 365. Information stored in Microsoft 365 isn't available publicly. Before you can interact with Microsoft Graph, you need to authenticate.
Microsoft Graph is secured with Microsoft Entra ID and uses OAuth to authorize applications to get access to users' data. After you connect your app to Microsoft Graph, users can sign in to your app by using their existing Microsoft 365 account. This capability frees you from having to implement authentication in your app and maintain users' credentials. It also benefits users by not having to use yet another credential to work with your app. Organizations can also control their employees' access to different applications, which is an important requirement for them.
Connect to Microsoft 365 by using SDKs
To help you connect your app to Microsoft Graph, Microsoft offers two software development kits (SDKs): the Microsoft Authentication Library and the Microsoft Graph SDK.
By using the Microsoft Authentication Library, you'll let users sign in to your app with their Microsoft 365 account. After they're signed in, the Microsoft Authentication Library will also help you get an access token that's needed to communicate with Microsoft Graph.
Although you can use the REST APIs directly, using the SDKs makes it easier to consume APIs. SDKs abstract away building requests and handling exceptions, which allows you to focus on building your app.
Next steps
Let's start by creating a simple app connected to Microsoft 365 that shows the name of the signed-in user.