Över last decades, a tremendous growth in wireless communication systems could be seen. This great success of wireless telephony and messaging systems, nowadays, is beginning to be applied to the world of personal and business computing systems. As a result, instead of facing with the some problems ör restrictions of the wired networks, people could access and share information nearly anywhere they want on the earth.This study is aimed to present the various aspects of wireless systems. in order to do this the history of wireless network systems is introduced, some defınitions are extracted, the answers to the some basic questions on why and where wireless networks can be applied are given and the definitions of protocols that have been developed are presented. Moreover, the benefıts of wireless networks, related confıgurations and standards, several underlying technologies, and some markets related with wireless systems are described. Comparisons between wireless and wired networks and among each other are also given.