[[AirPort]] is Apple's trade name for 802.11b ([[WiFi]]) wireless ethernet standard. The [driver ](http://www.ff.iij4u.or.jp/~ngc/eng/newtwave.htm] from Hiroshi allows some [[WiFi]] cards to work in the Newton. [[WaveLan]) Silver cards (by Lucent or other companies) are very popular and can be found for as little as $30.
Note that Apple-branded [[AirPort]] cards (such as those made for iBooks) will NOT work in a Newton - they are not PCMCIA compatible.
[[AirPortExtreme]] is available on Macs made since January 2003. This is the emerging 802.11g standard, a faster version that operates on the same frequency as 802.11b. 802.11a is not compatible with either b or g as it operates on a different frequency. The [[AirPort]] Extreme base stations support both the 'g' and the 'b' versions of the standard.
Newtons will not get much use out of 802.11g cards because they require faster connections than what the Newton's PCMCIA connection allows.