Hi @Alisha Jain Thanks for reaching out. API Management Service is an Azure PaaS service that acts as a proxy to your backend APIs (it can be on-prem/cloud). All requests from client applications first reach the API gateway, which then forwards them to respective backend services.
please refer the below docs for more information and basic understanding of APIM concepts
https://learn.microsoft.com/en-us/azure/api-management/api-management-key-concepts
https://learn.microsoft.com/en-us/azure/api-management/api-management-terminology
https://learn.microsoft.com/en-us/azure/api-management/backends
https://azure.microsoft.com/en-us/pricing/details/api-management/
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