New Release AZ-900 Microsoft Azure Questions

Azure App Service is a platform-as-a-service (PaaS) offering that lets you create web and mobile apps for any platform or device and connect to data anywhere, in the cloud or on-premises. App Service includes the web and mobile capabilities that were previously delivered separately as Azure Websites and Azure Mobile Services.

https://docs.microsoft.com/en-us/azure/security/fundamentals/paas-applications-using-app-services

Azure Cloud Shell is a browser-based shell experience to manage and develop Azure resources.

Cloud Shell offers a browser-accessible, pre-configured shell experience for managing Azure resources without the overhead of installing, versioning, and maintaining a machine yourself.

Being browser-based, Azure Cloud Shell can be run on a browser from a tablet that runs the Android operating system.

References:

re/cloud-shell/features

A network security group works like a firewall. You can attach a network security group to a virtual network and/or individual subnets within the virtual network. You can also attach a network security group to a network interface assigned to a virtual machine. You can use multiple network security groups within a

virtual network to restrict traffic between resources such as virtual machines and subnets.

You can filter network traffic to and from Azure resources in an Azure virtual network with a network security group. A network security group contains security rules that allow or deny inbound network traffic to, or outbound network traffic from, several types of Azure resources.