Dominic Tramontana has posted an interesting analysis of how the Reload glyph varies between browsers; take a look! Dominic asked me to post a screen shot I have of NCSA Mosaic, the first graphic web browser developed in 1993 by Marc Andreessen.
The grab I dug up is of a Novell web page, from early 1995. Here it is (click image to see the full page).
Back then, black on gray was the accepted way to write a web page, and the use of the red “book” images was a really impressive touch, I recall. We’ve come a long way…
In the old days electronic gear had on/off switches that were actually physical devices with two positions, like the light switch on a wall. Nowadays these have become a rare sight: with everything computerized, most state switching is done by pressing pushbuttons and keys, with the switching done by the logic circuitry or microprocessor.
The disadvantage of this solution is that (a) you can’t tell the state of a switch by looking at it, and (b) the act of switching can take a while as the computer goes about its activity. Even the basic act of turning a computer off now takes long moments (in the original home computers you hit the switch and power was simply cut off).
Here is a delightful exception to this trend: my latest Notebook, a Lenovo Thinkpad T61, has a slide switch on its outside for switching the Wireless radios on and off. Slide it to the right and the radio pops on instantly (as indicated by a green spot that becomes exposed under the slider). Slide to the left and the radio shuts down. Besides being fast and convenient, this is very useful when flying: if you believe in the inadvisability of having the Wireless on during flight, you can ensure it is off (and will stay off) before even turning the Notebook on. Absent this assertive hard switch, you’d need to turn the computer on, discover you left the radio on when you last put it into standby in the airport, and then you’d need to fumble with soft switches and dialogs to turn it off before the plane crashed. 
Reuse is good, right? And the notion conjures in most of us an image of linking code modules. Which is why I was astounded to run into the following case, while touring the beautiful island of Sicily.
Here you see your intrepid tourist in front of the Duomo (cathedral) of Siracusa, the city where Archimedes lived, engineered, and famously died defending his sand drawings. The baroque facade is a late addition (18th century) and nothing to write home about; but to its left there’s something unique and bizarre…
Below, left, is a close-up of the left wall of the Duomo. Note the embedded Doric columns, visible with their abaci and architrave (don’t worry, I had to look that up myself). These are also visible on the inside of the church, as seen in the photo at right.
So what’s going on? Well, the church was built in the 7th century AD. The columns, however, predate it by more than a millennium; they are what’s left of a Greek temple dedicated to Athena, which was built in the 5th century BC. Rather than follow the destroy-and-recycle method often applied to preceding cultures, the Christians reused the framework of the temple as is, filling in the spaces between the columns!
The evolution of the On/Off power switch symbol
We all know the symbol with a vertical line in a circle: it identifies the On/Off power switch. It occurred to me that this familiar symbol is evolving in a bizarre fashion.
Originally, switches had a lever or slider that could move to either of two physical positions. In those days the switch was marked with the word POWER and its positions with ON and OFF. Then, as switches became smaller and more globalized, the two words were replaced with 1 and 0, as seen even today on many rocker switches.
And then the ubiquity of microprocessors made it more economic to do everything with momentary pushbutton switches; the computer inside could take care of figuring whether you meant ON or OFF. And so, the button now needed an icon that conveys both options; I surmise that is when the familiar “1-inside-a-0″ symbol came into existence (if you know otherwise do share in the comments!) This round icon fit nicely on round buttons, and became ubiquitous.
But then we start to see the form shown in the two photos above right: a bastardized version combining the 1-in-a-circle with a 1 in the same symbol. This makes no sense at all – the correct representation would have been 1/0, for On slash Off. Instead we get On slash OnOff. Sloppy thinking…
Such erroneous contractions are often seen in spoken language – as in “IT technology”, which expands to “information technology technology” (there’s even a company by that name, and its slogan, amusingly, is “We make sense of IT“). But now we see the same error invading the more compact space of visual symbols…