Direct Sequence Spread Spectrum (DSSS) is a modulation technique used in wireless communication. It spreads the data signal over a wider bandwidth by multiplying it with a pseudo-random noise sequence. This process makes the signal more resistant to interference and jamming, enhancing the reliability of the communication. DSSS is commonly used in technologies like Wi-Fi and GPS. By spreading the signal, DSSS allows multiple users to share the same frequency band without significant interference, making it an efficient choice for crowded communication environments.