SaaS is also known as "On-Demand Software". It is a software distribution model in which services are hosted by a cloud service provider. These services are available to end-users over the internet so, the end-users do not need to install any software on their devices to access these services.

Features:

• Multi-tenancy model
• Automated provisioning
• Single Sign On
• Subscription based billing
• High availability
• Elastic Infrastructure
• Data Security
• Application Security
• Rate limiting/QoS
• Audit

Advantages:

• SaaS is easy to buy
• One to Many
• Less hardware required for SaaS
• Low maintenance required for SaaS
• No special software or hardware versions required
• Multi device support
• API Integration
• No client-side installation