RISC OS 3 was, unsuprisingly, the upgrade from RISC OS 2, which in turn was the first proper RISC OS after ArthurOS. RISC OS 2 came fitted in my A310, and being a poor student/layabout at the time I didn't really want to upgrade - until so much new software and PD came out that was RO3 only I had to.
RISC OS 3.0 came with the new A5000 computers, but was quite buggy - not a big surprise as it came on EPROM, so someone knew there'd be an upgrade not long after release. RISC OS 3.10 was the first upgrade, and I waited so long that 3.11 was available by the time I got round to it. I still didn't stump up full whack though, I was so cheap I said I had an A5000 and just paid the upgrade price. I still had to pay for a header card though.
Plain old RISC OS 3.11.
RISC OS 3.11
The image is of plain old RISC OS 3.11 after a clean reset. It has a 16 colour desktop at 640x256, although as the vertical pixels are rectangular it's the same apparent size as 640x512 which gave higher apparent resolutions with low resolution monitors and small amounts of memory. This rectangular pixel stuff first came into play with the 8bit machines like the BBC B for display on a TV without the need for interlacing, and of course there was the 32K memory limit - although this 32bit machine has been upgraded from 1MB to 4MB. This A310 is capable of proper 640x512 but came with a low-res monitor.
This machine also has an IDE hard drive fitted (called Cromwell, bottom left), which isn't standard on my A310 - although the 400 series had ST506 hard drives, the 300 series didn't, so I added a third party interface.
The main difference between the look of RISC OS 3 and RISC OS 2 is the addition of an Apps folder on the desktop. This contains programs and resources built into te ROM-based OS, so you always have a text editor, painting package etc. available even without any disks. RISC OS 2 had similar programs, but only if you had the Applications discs. The yellow and blue A task manager icon is now a green acorn too.
My usual RISC OS 3 desktop.
Living with RISC OS 3.11
My usual RISC OS 3 desktop. It's still not awe-inspiring by today's standards, but it has funkier icons including individual directory icons and antialiased filer text (these latter two using one small third-party patch module called Desktop+). The window furniture is in 3D too, although I have a plain pinboard to maximize the available memory. The screen mode is 256 colours with a hacked 832x288 (832x576) size. Note the virtual 24bpp colour display being shown using the built-in ColourTrans dithering.
As the boot sequence has been allowed to run you can see that this machine is on a network - Trinity is a remote drive accessed by an ancient Samba-like protocol called ShareFS. This particular machine is on a standard 10baseT, TCP/IP network, although older Econet networks were more common in schools.
The Task Manager
Configuration and Maintenance
One of the really nice things about RISC OS - apart from the easy-to-use GUI - is how easy it is to configure and maintain. The task manager gives a visual list of all running applications and other programs, and allows you to kill running processes or allocate more memory. For instance, if you need a RAM disk just click next to the RAM disc section and drag the red bar to the desired size, and a RAM disk appears.
Although a command line is available at all times from the desktop - or most text editors support Task Windows, which does the same thing in a window like Linux desktops - there's also a configuration application that allows you to do the same job more easily.
The RiscPC range came with later versions of RISC OS 3 installed - 3.5 was the first, then 3.6 with later machines, then 3.7 was introduced with support for StrongARM processors and fixing some brokeness that had crept in. The differences from a look and feel point of view were minor - a proper mode selection utility with colour and resolution rather than arbitrary mode numbers for instance - but added support for the new processors, disc controllers, graphics and sound chips, and, well, pretty much everything.
RISC OS 3.8 was available as a softloadable upgrade for developers to see how the new version would work on the RiscPC v2 (aka the Phoebe), which finally introduced things like very large hard disc support, long filenames (previously we'd been relying on a third party hack!), more than 77 files in a directory etc. However, Phoebe crashed and burned, taking Acorn with it, and then RISCOS Ltd. came along with RISC OS 4...