there is a thing you can download called skype that you can use on a computer if you have a microphone. it is free to call others that have downloaded it or 2 cents a minute to normal phones. just google skype.
if you are using a local phone then you get a prepaid calling card from a grocery store and use it. if you have your cell phone then check with your cell phone company for roaming minutes prices and see which is cheaper.
u can have a cell phone her by 200 egy.pound so u can call any where or download any software on ur laptop or buy prepaid cards choose what more suitable and cheaper to u enjoy ur trip to Egypt and Jordon