This guide walks you through the process of integrating Salesforce with a web application using a Connected App and the OAuth 2.0 JWT Bearer Flow. It covers steps like setting up the appropriate Salesforce user permissions, creating a self-signed certificate, configuring the Connected App in Salesforce, and implementing authentication and data exchange routes in a Next.js environment. The goal is to securely fetch and post data to Salesforce from your app without requiring user login each time.