Web role is basically an Azure Cloud Service role.
There are two types of Azure Cloud Services roles. The only difference between the two is how your role is hosted on the VMs:
Web role: Automatically deploys and hosts your app through IIS.
Worker role: Does not use IIS, and runs your app standalone.
For more info refer to https://docs.microsoft.com/en-us/azure/cloud-services/cloud-services-choose-me
Hope this helps!
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