Nanosensors have emerged as a promising technology in various fields, offering valuable insights into the detection and monitoring of a wide range of substances at the nanoscale. Nanosensors have gained significant attention in the field of sensing applications due to their unique physicochemical properties that are dependent on their size at the nanometer scale. These materials, with their distinct characteristics, hold great promise for various sensing applications. The nanosensor exhibits the capability to transmit data and information pertaining to the behaviour and characteristics of particles at the nanoscale, while manifesting this information at the macroscopic level. Nanoparticles exhibit distinct chemical, mechanical, and optical characteristics that render them highly suitable for deployment in nanoscale sensor applications. In this discourse, we shall delve into the advancements witnessed over the course of recent years pertaining to nanosensors, which have exhibited diverse applications.