SaaS (Software as a Service) is a cloud computing service model in which software applications are delivered over the internet, rather than being installed locally on a user’s computer or on-premises server.
Key Characteristics of SaaS:
Hosted in the cloud: The software runs on the provider’s servers.
Access via web browser or app: Users don’t need to install or maintain the software locally.
Subscription-based model: Usually paid monthly or annually.
Automatic updates: The provider manages updates, patches, and maintenance.
Scalable: Can handle more users or data as needed without user intervention.
Examples of SaaS:
Google Workspace (Gmail, Docs, Sheets)
Microsoft 365
Salesforce
Zoom
A hypervisor is software, firmware, or hardware that creates and manages virtual machines (VMs). It allows multiple operating systems to run simultaneously on a single physical computer by abstracting the hardware resources and allocating them to each VM. Essentially, it acts as a layer between the physical hardware and the virtual machines, enabling virtualization.
There are two main types of hypervisors:
Type 1 (Bare-Metal Hypervisor):
Runs directly on the physical hardware.
No underlying operating system is needed.
Examples: VMware ESXi, Microsoft Hyper-V, Xen.
Type 2 (Hosted Hypervisor):
Runs on top of an existing operating system.
The host OS manages the hardware, and the hypervisor runs as an application.
Examples: VMware Workstation, Oracle VirtualBox.
Key point: A hypervisor enables virtualization, making it possible to run multiple isolated OS environments on the same hardware, improving resource utilization and flexibility.
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