Have you got the time? If you're wearing a smartwatch, then you've got plenty more besides as the humble hourglass has evolved far beyond just hours, minutes and seconds.
Every decade since the digital age has seen attempts to cram more information onto our wrists - some have been more successful than others but all have had an influence on the connected, intelligent watches that are vying for our attention today.
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Smartwatches have actually been around a lot longer than you think â it's just that no one thought to call them smartwatches.
1972: Pulsar Time Computer
The first LED watch was mass-produced in the US by The Hamilton Watch company. Its sole purpose was to tell the time in a digital format and the only sensor it contained was one that adjusted the brightness of the LEDs so that they could be read in different light conditions. However, overnight, it changed people's perceptions of how a watch could tell the time.
At Xerox's Research Center in Palo Alto a physicist named Nick Sheridon was working on an alternative to liquid crystal display screens that would be easier to read and use less power. Sheridon called it "electronic paper" and it would later become the display tech of choice for both Sony and Pebble.
1985: Seiko RC-20 Wrist Computer
The Japanese company continued to drive innovation in the eighties with this first generation piece that was touch sensitive and could be linked to your computer with an accompanying cable. You could code on your PC and then download the application to your watch, however there was only 8K of storage, so programming was limited.
1993: IBM Simon Personal Communicator
Even though it featured a less sensitive, resistive touchscreen interface, this telecomm brick from the early nineties was the first product to combine touchscreen tech with a phone. It also fully realised the multi-functionality that would be seen in all later efforts incorporating email, calendar, address book, calculator and a sketchpad.
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1994: Casio VivCel VCL-100
(Picture credit: semiwiki.com)
Casio were always out front when it came to pushing what a watch was capable of, but we're not concentrating on calculator watches and multiple time zone displays here. This model from the VivCel range had an antenna that detected when your phone was ringing and alerted you by vibrating on your wrist.
The company that fine tuned gesture based keyboards and screens spent years perfecting the art of multi touch recognition with products like the TouchStream keyboard and the iGesture Pad. Proof that they were doing something very right came in 2005, when Apple bought them.
2000: IBM WatchPad 1.5
A collaboration with Citizen, the watch ran the Linux operating system and featured a fingerprint security scanner, accelerometer and even had the emergent Bluetooth. The downside: battery life was limited to six hours.
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2004: Microsoft SPOT
Standing for Smart Personal Object Technology one of Bill Gates's pet projects sought to provide news flashes, including sport, weather and finance over one-way FM waves. Its monochrome, battery saving, screen predated the Pebble but functionality was severely limited as was the future of SPOT, which was discontinued in 2008.
This groundbreaking watch, with a limited edition run of 500 pieces, took full advantage of e-paper's properties and was ultra high contrast, had low power consumption and was wafer-thin â hence the bracelet design. It was the final stepping-stone before the giant leap towards the smartwatch explosion.