Science and Engineering Forum

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802.11 In 1997, the Institute of Electrical and Electronics Engineers (IEEE) created the first WLAN standard. They called it 802.11 after the name of the group formed to oversee its development. Unfortunately,  802.11  only supported a maximum network bandwidth 2 Mbps, too slow for most applications. 802.11b IEEE expanded on the original 802.11 standard in July 1999, creating the 802.11b specification. 802.11b supports bandwidth up to 11 Mbps, comparable to traditional Ethernet. 802.11b uses the same unregulated radio signaling frequency ( 2.4 GHz ) as the original 802.11 standard. Vendors often prefer using these frequencies to lower their production costs. Being unregulated, 802.11b devices can have interference from microwave ovens, cordless phones, and other appliances using the same 2.4 GHz range. However, by installing 802.11b devices an adequate distance from other appliances, interference can easily be avoided. Pros of 802.11b  - lowest cost; signal range is good an

This column was first published in Slate in 2009. I always charge my phone, laptop, and MP3 player overnight—even though it only takes a few hours to get them fully charged. Should I be losing sleep over this? Would it better for me to charge my electronics during my morning commute, by plugging them into the car charger? As far as environmental sins go, you can file this one in  the venial category . Yes, charging your gadgets for longer than necessary wastes some energy. Will better habits significantly reduce the footprint of your techno-lust? Not likely. Let's start with the most ubiquitous mobile device—the cell phone. What happens if you leave yours plugged in all night? According to  measurements from Lawrence Berkeley National Laboratory , the average cell phone draws 3.68 watts of power from the outlet while it's charging and 2.24 watts when charged. Let's take the worst-case scenario and assume that you're over-juicing a charged battery for t