Why signal is spread in dsss?

In Direct Sequence Spread Spectrum (DSSS), the signal is spread to increase its resistance to interference and jamming, enhance security, and allow multiple users to share the same frequency band without significant interference. By spreading the signal over a wider bandwidth using a pseudorandom noise (PN) sequence, DSSS makes it more difficult for unauthorized receivers to detect and decode the transmission. This spreading also improves the system's robustness against multipath fading and enhances the overall reliability of the communication.