In today's world, the internet provides your customers with a wide variety of services to help them run their business efficiently. Once your application is released, your customers will want to integrate many of these services into your application's services as well. While there are significant application management optimizations and data security benefits to customers choosing multiple applications based on the same platform, the reality is that other services and platforms exist and may already be a part of your customer's infrastructure, which is why we need to use External Services.

Fortunately, Salesforce understands this and embraces the integration of external services in a variety of ways, regardless of whether it is an external process calling one of your application services and/or existing platform services (inbound) or the need to invoke an external service within the Lightning Platform (outbound). The platform allows you to package such external integrations and/or your customers to access easy-to-use tools and products that fast-track the process, leveraging the fact that your application is built on a platform; those tools are easier to use as they inherently understand your application's data and code and how to expose it.

In this chapter, we will explore working with external services that represent external processes, as well as external data to be integrated. We will cover the following topics:

• Understanding inbound and outbound integrations
• Managing inbound integrations with Connected Apps
• Options for outbound integrations
• Managing outbound integrations with Named Credentials
• Invoking outbound integrations 
• Accessing external services via External Services
• Accessing external data seamlessly via External Objects

To help with this process, we will use a variety of existing services and some sample services hosted using the Salesforce Heroku platform. Let's start with the first topic: inbound and outbound integrations.