So as most of you know, my day job is working at one of the big boys in cloud infrastructure hosting. As such I've gotten to learn a TON about different cloud types, and etc... As part of my big drive to do a startup, I've gotten the run down of a few cloud providers, and have been trying to work out who gives the best bang for buck for my startup idea. In the meanwhile, I figured I'd do a post on different *major* types of clouds, and some examples of each. So without further ado, here're the major types of clouds :

Infrastructure as a Service or IaaS

This is the big one, and probably the one with the most examples right now. Essentially, you can look at this like an abstracted utility style version of what you have in your company data centre, and/or even your desktop type computing is moving into the IAAS model. Usually, this comprises of computing, memory, and storage in the cloud in different shapes, sizes, and/or forms.

Some examples of IaaS clouds are:

Rackspace Cloud (Cloud Servers, Cloud Files, Cloud Load Balancer), and then of course Amazon AWS (Amazon EC2, Amazon S3, Amazon EBS).

Note: This is also usually what gets melded into the form of 'Public', 'Private', and 'Hybrid' Clouds. Public being the above mentioned two, Private being a dedicated installation (usually), and then Hybrid being a mix of the two (again, usually).

Platform as a Service or PaaS

This is basically something along the lines of 'you load your app on our servers. We care about the servers, and the scaling, and you care about the app'. It's another level of abstraction above the IAAS model which allows you to focus on your application, and less on your infrastructure, while of course being a huge positive for the developer focused market, this isn't always the best option and in many cases creates vendor lock-in though a reliance on the underlying platform, and as such, the vendor. This is also one of the easiest ways to get locked into a platform, although over time the vendors are moving to a less 'one-sided' model on this front, and starting to adopt more open standards (such as SQL for example).

Some examples of PaaS clouds are :

Heroku, EngineYard App Cloud, Google App Engine.

Software as a Service or SaaS

This is the last line of Cloud Vendors. Essentially, this is where a company produces software that makes sense for you to allow them to run completely. The only thing you need to do in these cases is pay for them, possiby integrate with them, and then of course use them. This of course has the highest possibility of vendor lock-in with your data residing inside their application, but also this has the least outlay as you don't have to pay to have an app built, or keep it running, you simply use it. This is proving to be the most popular for buisness applications due to the instant on nature of the applications.

Some examples of SaaS clouds are :

Google Apps, ZenDesk, SalesForce

Comments, Questions, Ides?