Episode 22 of the Azure Zero to Hero series demonstrates event-driven serverless architecture on Azure. It builds on Day 21's theory, showing how to create and trigger serverless functions using Azure Blob Storage. Code is available on GitHub. Day 24 will cover resume building with project examples. This segment provides a clear explanation of serverless architecture, contrasting it with traditional virtual machine hosting. The example of a rarely accessed Java application highlights the cost-saving benefits of serverless, where resources are only allocated during active use. This segment summarizes the core difference between virtual machine and serverless approaches. It emphasizes the cost-saving aspect of serverless, where you only pay for the compute time used, unlike virtual machines that incur costs even when idle. The segment also touches upon the broad applicability of serverless across various use cases. This segment details a practical DevOps scenario where a serverless function is triggered by file uploads to Azure Blob Storage. The example focuses on notifying the team when files exceed a size limit, illustrating how serverless functions automate tasks and optimize resource usage.This segment explores another serverless application use case involving Azure Queues. It explains how serverless functions can process user requests from a queue, highlighting the efficiency compared to constantly running virtual machines. The discussion includes cost optimization and the asynchronous nature of queue-based processing. This segment sets the stage for the practical demonstration. The speaker explains the approach of using a simplified use case to make the concept accessible to beginners, promising more advanced scenarios in future videos. This provides context and expectations for the upcoming practical demonstration.This segment begins the practical demonstration by guiding viewers through the Azure portal. The speaker emphasizes using the Azure CLI for configuration and highlights potential challenges when using a free tier subscription, offering valuable advice for those following along. This segment differentiates between Azure Functions (where code executes) and Function Apps (which act as wrappers managing authentication, authorization, logging, and custom domains for functions). It highlights the Function App's role in centralizing control and management aspects of serverless functions.The presenter outlines three methods for creating Azure functions: using the Azure portal (recommended for beginners), Visual Studio Code, and the command-line interface (CLI). The advantages and disadvantages of each approach are discussed, emphasizing the simplicity and ease of use of the Azure portal for beginners.This segment focuses on creating a serverless function within the Azure portal, explaining the "Develop in portal" option and its implications for UI access. It also briefly touches upon alternative development environments (Visual Studio Code and CLI) and offers to elaborate on these in future content.The presenter explains different trigger types for Azure functions, including HTTP triggers and blob storage triggers. The segment emphasizes the concept of event-driven architecture and the choice between manual and automatic function invocation. The use of a blob trigger as an example is introduced.This segment details the process of setting up a blob trigger, specifying the storage account path to monitor for file uploads. It clarifies the significance of the path parameter and how it determines which files trigger the function. The presenter explains how to handle file names that are not known in advance. This segment showcases the features of a created Azure function, including code access, integration views, and monitoring capabilities. It also highlights performance and feature limitations encountered when using a free trial Azure subscription, advising viewers to consider a paid subscription for optimal experience.