The development of the location based services and rapid advancement in communication services has extensively increased the researcher's interest in an area of the localization systems. In the context-aware computing, one of the key capability is location determination. At present, indoor location-based systems use various techniques like Time of Arrival (TOA), Time Difference of Arrival (TDOA), Angle of Arrival (AOA) and Received Signal Strength Indicator (RSSI). This work focus on the review of different active and passive indoor localization techniques developed over the period of time. The common localization techniques include the active localization systems as the person being detected and tracked carries the tag or any device attached. The other class called passive localization stand for the locating the person without the use of any tag or device. The analysis of the localization systems is based on the wireless technology applied, accuracy and precision positioning algorithm, scalability, complexity and costs. This paper compares different localization systems by analyzing pros and cons.