The mouse has come a long way since Doug Engelbart's team of engineers designed the first model back in 1964 . The twin wheels originally used for vertical and horizontal tracking were soon replaced by a roller ball, which in turn gave way to today's optical mice. The cable has evolved too, with old-style serial connectors giving way to USB in the mid-90s, and then becoming optional with the arrival of wireless connectivity. Today's mice connect to your Mac using Bluetooth or USB wireless, both of which use radio technology on the 2.4GHz waveband. The advantages of wireless connectivity are obvious. With no cables to trail across your desk, you can place your mouse wherever you like. Modern Macs offer integrated Bluetooth for connecting to compatible peripherals, and non-Bluetooth wireless mice come bundled with a USB dongle that acts as a receiver. So using a Bluetooth model frees up a USB port - though most wireless dongles are small and compact, and can be connected through your keyboard's USB port. The primary disadvantage of wireless mice is that they need batteries, with Bluetooth devices being a little more power-hungry. Also, many gamers prefer the extra precision offered by a cabled USB connection
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