AWS, Azure, GCP and openstack are all cloud platforms that give you a variety of hosting features and a lot more. All of them differ a great deal and today are used quite a lot in many places. There are a lot of other providers but none comes as close to AWS, Azure and GCP when it comes to features and services offered.
AWS (Amazon Web services) despite the name offers a plathora of solutions and services. I mention AWS first because AWS is the most unique out of the bunch. AWS focuses on building the lego pieces you need and letting you assemble them yourself into the solution you want to create. This is why there exist certifications well considered around the world that basically related to the services AWS offers, knowing them and picking the right pieces needed for your solution as you compare features, costs and more. AWS is very detailed in features and billiong for every component it offers. Think of AWS like lego, it has so many different pieces that you can use to build something. If you need something that AWS doesnt offer, they will create that solution for you. The details of services offered by AWS makes them a good choice in comparing to lego since they have so many different services that can be combined to great detail and effect in creating a solution.
Openstack mimics the intricate details of AWS in the features it offers when it comes to tracking usage for example, however openstack is focused on hosted solutions that you host yourself. Most of the common things you need are available in openstack, and you can host it yourself. Its a bit like hosting your own mini AWS but with a fraction of its features, mostly common features such as VM hosting, container hosting and a few other things even the provisioning of bare metal servers as well. Quite often you cant use openstack by itself, but rather can be combined with other things like Ceph for storage management and replication. The key thing that defines openstack is the ability to even without containers make the management of hosting clusters more redundant, allowing your applications to survive from downtimes of any machine or component. For example with the help of ceph, should a machine go down the VMs can instantly be relaunched on another server whereas should a proxmox cluster go down all of a sudden, the VMs will be inaccessable and unavailable even if the storage is located on a different server.
Azure and google cloud are similar in nature but different from openstack and AWS. They are geared more towards complete solutions rather than a variety of different pieces for you to put together and are focused on their ecosystems. Azure has the microsoft ecosystem consisting of various services just as google does, from office software to email domain management and much more. For instance azure allows you to have microsoft manage your active domain deployment instead of you having to purchase microsoft server licenses and provide the servers upfront, in addition these providers also provide hosting services just like with some of aws services. These providers are less like aws and more about offering an ecosystem towards fulfilling your needs instead.
it is therefore illogical to use Azure and AWS together for example as they both have very different focuses towards an organisation’s needs. One might combine openstack with AWS for a compatible hybrid environment but AWS, GCP and Azure all offer multiple datacenters in different countries, allowing you to have redundancy with just 1 provider. With Azure you may find it better to deploy microsoft servers and using them together with azure as a hybrid cloud solution. Google also have their services centered around what they offer outside of the cloud from android to chromebooks, google’s own office suite, their business software suite and much more that cater towards individual and organisational needs.
Typically it is expected to only use 1 of the big 3 providers and if in a hybrid solution to implement their respective ecosystems instead. While google and microsoft focus on offering similar solutions in their ecosystem, aws focuses on offering pieces to choose from instead of an ecosystem. Sure amazon does have their own devices but it pales in comparison to the number of hardware and software solutions offered by google and microsoft for fulfilling the basic computing needs of both individuals and organisations, this before even considering the cloud either. It may not make sense in cost to use more than 1 cloud provider, but rather to use a compatible hybrid solution instead if need be as using more than 1 provider will only complicate your setup.