> For the complete documentation index, see [llms.txt](https://gchandra.gitbook.io/data-warehousing/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://gchandra.gitbook.io/data-warehousing/cloud/types-of-cloud-services.md).
# Types of Cloud Services
#### SaaS
Software as a Service
Cloud-based service providers offer end-user applications. Google Apps, DropBox, Slack, etc.
* Web access to Software (primarily commercial).
* Software is managed from a central location.
* Delivery 1 - many models.
* No patches, No upgrades
When not to use
* Hardware integration is needed. (Price Scanner)
* Faster processing is required.
* Cannot host data outside the premise.
#### PaaS
Platform as a Service
Software tools are available over the internet. AWS RDS, Heroku, Salesforce
* Scalable
* Built on Virtualization Technology
* No User needed to maintain software. (DB upgrades, patches by cloud team)
When not to use PaaS
* Propriety tools don't allow moving to diff providers. (AWS-specific tools)
* Using new software that is not part of the PaaS toolset.
#### IaaS
Infrastructure as a Service
Cloud-based hardware services. Pay-as-you-go services for Storage, Networking, and Servers.
Amazon EC2, Google Compute Engine, S3.
* Highly flexible and scalable.
* Accessible by more than one user.
* Cost-effective (if used right).
#### Serverless computing
Focuses on building apps without spending time managing servers/infrastructure.
Feature automatic scaling, built-in high availability, and pay-per-use.
Use of resources when a specific function or event occurs.
Cloud providers handle the deployment, and capacity, and manage the servers.
**Example**: AWS Lambda, AWS Step Functions.
### Easy way to remember SaaS, PaaS, IaaS