Windows 10 S is a version of Windows 10 that Microsoft appears to be pitching at would-be Chromebook buyers. It was was announced on 2 May and is a free upgrade for all schools on PCs running genuine Pro versions of Windows

So far consumers will have seen it preinstalled only on devices such as the Surface Laptop. For those who'd prefer the full-blown Windows 10, Microsoft is allowing buyers to switch to Windows 10 for free on their Surface until March 2018. Previously it had said the free switch offer would end in December 2017.

Now, though, Windows 10 S is also available via the Insider channel for beta testers. In order to install this you must have a PC running Windows 10 Pro or Enterprise, although keep reading before you do this.

What's the difference between Windows 10 and Windows 10 S?

The key change in Windows 10 S over standard Windows 10 is that you can download and install apps only from the Windows Store, which helps make it ultra-secure. Apps then run in a safe container that prevent them from affecting overall performance of the machine.

Microsoft says Windows 10 S laptops offer the same performance on their first day out of the box as they do their last day of life.

If necessary, teachers can switch to Pro mode to install other apps, but children will not have this luxury. Upon attempting to install a program from an .exe file a warning pops up that says the app cannot be installed, offering alternatives within the Store.

While Windows 10 S can run any web browser found in the Windows Store, Microsoft is keen to point out that its own Edge browser features that were designed with students in mind, such as annotation and sharing for research purposes.

Windows 10 S machines can support devices and peripherals in the same way as can standard Windows 10 devices including, for example, the Ohbot Arduino robot designed to help kids learn coding and VR headsets.

Windows 10 S laptops start up very quickly - in around 15 seconds - which means students can be ready to work much faster.

The settings for a group of Windows 10 S laptops can be centrally managed, allowing you to quickly make changes on every machine. Teachers can also set up a pre-configured environment in as little as 30 seconds by plugging in a USB stick to each machine.

Microsoft also announced that Office 365 Personal will be coming to the Windows Store soon, while Office 365 for Education will be free with Microsoft Teams. Microsoft InTune for Education will also be available from today, the company announced.

An added bonus for students using Windows 10 S is a one-year subscription to Minecraft Educational Edition.

Which laptops and PCs come with Windows 10 S?

Windows 10 S is aimed at students and teachers, and is available on budget laptops priced from just $189 - just in time for the new school year.

Microsoft's hardware partners include Acer, Asus, Dell, Fujistsu, HP, Samsung and Toshiba, though Windows 10 S will run on any laptop - from ultra-low-cost models to high-spec machines, including Microsoft's own Surface range and the Surface Laptop.

Microsoft has previously experimented with cheaper versions of Windows for low-cost computers, including Windows 8 with Bing, which was in essence just Windows 8 with Microsoft Bing as the default browser, and Windows RT, which was designed for ARM processors and ran only the Modern user interface, so you couldn't install any desktop apps.

What does the S stand for?

According to Microsoft, the S in Windows 10 S stands for three things:

• Streamlined for simplicity

• Secure

• Superior performance

When is the Windows 10 S release date?

Microsoft says Windows 10 S will be available on new laptops from its partners this summer, which means they will be in student hands for the next school year.

How much does Windows 10 S cost?

For schools already running Windows Pro PCs the new OS is free. New laptops running Windows 10 S will be available from $189.

Which new laptops run Windows 10 S?

The best example of a Windows 10 S laptop is probably Microsoft's own Surface Laptop. It is available to  buy now, but at £979 in its cheapest incarnation you might prefer to look at some of the less expensive budget Windows 10 S laptops below.

Microsoft Surface Laptop

Surface Laptop

Toshiba Portégé X20W-D

Toshiba Windows 10 S laptop

Samsung Notebook M

Samsung Windows 10 S laptop

HP Probook x360 11 G1 EE

HP Windows 10 S laptop

Fujitsu LIFEBOOK P727

Fujitsu Windows 10 S laptop

ASUS Vivobook W202

Asus Windows 10 S laptop

Acer Travel Mate Spin B1

Acer Windows 10 S laptop

Dell Latitude 11 3000 Series 3189 2-in-1

Dell Windows 10 S laptop