A beginner’s guide to cloud storage

Even if you don’t read computing magazines for fun, or contribute to the r/coding pages on Reddit, you’ll have heard the phrase “cloud storage” being bandied around.

To the uninitiated, this might seem like a baffling concept. Apart from rainwater, clouds aren’t renowned for their storge capacities, or for being especially accessible.

Yet many of our online activities are underpinned by this relatively modern method of data storage.

So what is cloud storage? How does it work, and why do we need it?

What is cloud storage comprised of?

There are two main locations where you can store information produced by a computer or other electronic device.

The first is on the device itself – known as local storage. The other is remotely, which generally means ‘in the cloud’.

The cloud itself is simply a term for instantly accessible data storage, saved away from a local terminal or device so it can be viewed and edited from other web-enabled machines.

Cloud storage consists of warehouses crammed with giant hard disc drives known as servers, operated by specialist hosting companies or blue-chip brands like Amazon.

What is cloud storage used for?

In truth, almost anything which isn’t stored on a local device. Examples include:

Is it safe?

Each physical data server has a real-time backup stored in another location, in case anything catastrophic happens to it. This is known as redundancy.

In truth, it’s hard to think what could actually happen.

Servers are stored in warehouses with backup power, heating and cooling systems, alongside sprinklers and round-the-clock security personnel.

These warehouses are usually in obscure locations, and they’re not advertised with signage because the vast amounts of data they contain might attract the wrong sort of attention.

If anyone did break into a cloud storage facility, they’d be immediately deterred from making further progress by military-grade security.

Even professional hackers have struggled to penetrate the digital shields surrounding modern data centres, so personal or small business data will be completely secure.

Cloud storage seems very cheap. Is that a worry?

Not at all. Cloud storage is often for supplied free as part of a wider service, or at a cost of pennies per month, because companies in this industry can harness vast economies of scale.

The average data centre extends to around 100,000 square feet, with each individual server occupying less than one square foot of floor space.

Within that relatively compact footprint, one server HDD may be able to host 16 terabytes of content.

With the average website page occupying around three megabytes, you could store roughly five million webpages on one server disc.

Each customer receives a dedicated portion of a server, which nobody else can access. This is known as shared server space, but only the host knows who else has space on the same server.

Even if a hacker somehow managed to access Company A’s portion of a shared server, they’d be unable to view or access the files stored by Companies B-Z.

Larger businesses sometimes acquire their own servers (known as dedicated hosting), gaining full control over access, safety and maintenance.

For the rest of us, shared cloud storage will be perfectly satisfactory.