How the cloud works

We’ve all heard people referring to ‘the cloud’ but it’s often not clear what that actually means. What is the cloud?

Put simply, the cloud refers to services that you access through the internet. You’re probably using it without realising it. Any time you store information online, rather than on your computer, you’re using the cloud.

For example, when you save documents on your computer, they’re stored on your computer’s hard drive. When you save them to the cloud, you’re storing them on someone else’s hard drive.

Common cloud services include:

  • storage services, like Dropbox or Google Drive, where you can store documents
  • email services, like Gmail or Yahoo mail, for example
  • gaming services, such as PlayStation Now
  • social networks, like Instagram, Facebook and YouTube.

How it works

Cloud services providers have a network of servers (computers) that they manage and maintain, situated in data centres. Most service providers have servers all over the world. They’re not reliant on only one server in one place. This means that if there’s a disaster — like a fire — at one data centre, your data isn’t lost. You can access it through another server somewhere else instead without doing anything differently.

You connect to the servers through:

  • your internet browser — like Chrome, Firefox, or Internet Explorer
  • applications – like the Facebook app, YouTube app or computer games.

As long as you have an internet connection, you can access the cloud at any time, and on any device. This could be your computer, your phone, your tablet, or your games console. You don’t have to carry a particular device around with you to be able to access the cloud.

In most cases, you access cloud services through an account that’s unique to you. Think of your email account, your Facebook account, or even your Netflix account. You have a login for these accounts that helps keep your data private and accessible only to you. It’s important to make sure you have a different password for each one of your cloud based accounts. Don’t use the same password for your Facebook account as you do for Netflix, for example. That way, if someone gets access to one of your account passwords, they won’t get access to your other accounts as well.


  • It’s quick and easy to set up a cloud account online.
  • If you have a lot of data or information, you don’t have to store it all on your own computer — you can store it in the cloud instead. This is often easier and cheaper than installing more storage space on your computer. Some companies, like Dropbox and Google Drive, give you a certain amount of storage space for free. If you do pay for storage, the cost is usually quite small. Storing your data in the cloud is like renting storage space on someone else’s computer or hard drive.
  • Cloud service providers:
    • back up your information for you
    • keep their servers updated, and
    • may use encryption to help keep your information safe and secure.
    They also store your information on more than one server. If there’s a problem with one server, your information is still available through another.
  • Storing information in the cloud gives you a convenient way to access it. You can access your accounts and your data on any device at any time, as long as it’s connected to the internet. This means you always see the most current version of anything you have stored online. For example, you can edit a document at home on your laptop, and then pick it up at work on your computer there. You could even collaborate on it with your workmates.


  • If you don’t have an internet connection, you can’t access any data you have stored in the cloud. For example, if you can’t connect to the internet, you can’t access Facebook, your email or any documents you store online.
  • When you use the cloud, you’re relying on your service provider to keep your data safe and private. Companies like Google have security measures in place to protect your data. But, nothing’s bulletproof. If there’s something that you really don’t want other people to find, don’t store it in the cloud. Store it offline somewhere else instead.
  • Businesses in particular can see the cloud as a risk. Using the cloud means handing over confidential data held by your business to a third party. This could put it at risk of unauthorised access and could breach your data handling procedures.
  • If your cloud services provider stops operating unexpectedly, you’ll lose access to any information stored with them.

Unauthorized access explained

How data breaches work

Visit CERT NZ for more information. 
Visit ACSC for more information.