As Tim Berners-Lee was working on a NeXT computer, that is the environment simulated. NeXT machines we’re not that common, having been launched in 1988 at a cost of US$6,500 (equivalent to $13,800 or so now).
When you go to the site, you could try clicking around on the links on the opening document—remembering that you need to double-click on links to activate them—but you’ll quickly find that most of them don’t work. They’re long gone. So it’s probably going to be more fun to open a new page to use as your starting point.
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, or even use Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for MakeCode, CircuitPython, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.