  Movable antenna (MA) technology is a recent development that fully exploits
the wireless channel spatial variation in a confined region by enabling local
movement of the antenna. Specifically, the positions of antennas at the
transmitter and/or receiver can be dynamically changed to obtain better channel
conditions for improving the communication performance. In this article, we
first provide an overview of the promising applications for MA-aided wireless
communication. Then, we present the hardware architecture and channel
characterization for MA systems, based on which the variation of the channel
gain with respect to the MA's position is illustrated. Furthermore, we analyze
the performance advantages of MAs over conventional fixed-position antennas, in
terms of signal power improvement, interference mitigation, flexible
beamforming, and spatial multiplexing. Finally, we discuss the main design
challenges and their potential solutions for MA-aided communication systems.
