AWS primarily utilizes two types of virtualization:

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1. Paravirtualization (PV):

Guest operating systems are aware they are running in a virtualized environment.
The guest OS interacts directly with the hypervisor, bypassing the host OS. AWS Training in Pune
Offers better performance than full virtualization, but limited hardware support.  
Primarily used for Linux-based instances.
2. Hardware-Assisted Virtual Machine (HVM):  

Guest operating systems are unaware they are running in a virtualized environment.
The hypervisor emulates hardware to the guest OS, providing a more realistic environment.  
Supports a wider range of operating systems, including Windows and Linux.    AWS Course in Pune
Offers better hardware compatibility and support for advanced features.
In recent years, AWS has primarily shifted towards HVM virtualization, which provides better performance, flexibility, and compatibility with a wider range of operating systems and hardware features.