Cloud computing means renting computing resources, such as servers, storage, databases and software, over the internet instead of buying and running your own hardware. You use what you need, when you need it, and usually pay by the month or by usage. Business email, online accounting, file sharing and web hosting are all everyday examples of cloud services.
How cloud computing works
A cloud provider runs large numbers of servers in data centres. Software called a hypervisor splits each physical server into many virtual machines, and storage and networking are pooled in the same way. When you sign up for a cloud service, the provider gives you a share of that pool. You reach it over the internet from a browser, an app or a command line.
Because the hardware is shared and managed by the provider, you do not need to buy servers, find space for them, keep them cool or replace failed disks. That work becomes the provider’s job.
The five defining features
The widely used definition from the US National Institute of Standards and Technology (NIST) lists five characteristics:
- On-demand self-service: you can set up resources yourself, without waiting for someone to install hardware.
- Broad network access: services are available over the network from laptops, phones and other devices.
- Resource pooling: the provider serves many customers from shared hardware, with each customer’s data kept separate.
- Rapid elasticity: you can add or remove capacity quickly as demand changes.
- Measured service: usage is tracked, so you pay for what you use or for a defined plan.
The three main service models
Infrastructure as a Service (IaaS)
You rent virtual servers, storage and networking, and you manage the operating system and everything on top of it. A virtual private server (VPS) is a common example. IaaS gives the most control, but you are responsible for updates, security and backups inside the server.
Platform as a Service (PaaS)
The provider manages the servers and operating system, and you deploy your application onto a ready-made platform. Developers use PaaS to build and run apps without managing servers. Managed hosting for a specific platform, such as WordPress, works in a similar way.
Software as a Service (SaaS)
You use finished software through a browser or app. The provider handles everything underneath. Webmail, online office suites and accounting software are SaaS. This model needs the least technical work from you.
Deployment models
- Public cloud: services offered to many customers over the internet on shared infrastructure.
- Private cloud: infrastructure used by one organisation, either in its own building or hosted by a provider.
- Hybrid cloud: a mix of public and private, with data and workloads moving between them.
- Multi-cloud: using services from more than one provider, often to avoid depending on a single one.
Benefits for businesses
- Lower upfront cost: you pay a regular fee instead of buying servers.
- Scale when needed: you can move to a bigger plan as your business grows, without replacing hardware.
- Access from anywhere: staff can work from the office, from home or on the road.
- Less maintenance: the provider handles hardware failures, power and cooling.
- Better resilience: good providers keep backups and use redundant hardware, which is hard for a small business to match on its own.
Risks and things to check
Cloud computing is not automatically safe or cheap. Before you choose a provider, check:
- Security responsibilities: the provider secures the infrastructure, but you are usually responsible for passwords, user access and, on IaaS, the server software. This is often called the shared responsibility model.
- Data location: know which country your data is stored in, especially if you handle personal data.
- Costs: usage-based billing can grow quickly. Fixed-price plans are easier to budget for.
- Internet dependence: if your connection goes down, you lose access. A backup connection helps.
- Uptime commitment: look for a published service level agreement. Tremhost’s SLA sets a 99.9% monthly availability target for hosting, email and servers.
- Getting your data out: make sure you can export your data if you change provider.
Cloud computing and web hosting
Web hosting is one of the oldest forms of cloud service. Shared hosting is close to SaaS or PaaS: the host manages the server and you manage your site. A VPS is IaaS: you get a virtual server with root access and manage it yourself. Read what web hosting is for more on the difference.
Frequently asked questions
Is cloud computing the same as the internet?
No. The internet is the network that connects devices. Cloud computing is a way of delivering computing resources over that network.
Is my data safe in the cloud?
It can be, if the provider runs good security and you do your part: strong passwords, two-factor authentication, careful user access and regular backups. Security is shared between you and the provider.
Is a VPS a cloud server?
A VPS is a virtual machine on a shared physical server, which is the basic building block of IaaS cloud. Some providers use the term “cloud server” for VPS plans that can be resized or moved between hosts more easily.
What cloud services does a small business usually need?
Most start with business email, website hosting and file storage or backup. As they grow, they may add a VPS for custom applications.
Next step
If you need your own virtual server, Tremhost KVM VPS plans give you dedicated cores, NVMe storage and full root access, with data centres in Johannesburg, New York, Miami, Germany and France.
