Nanotechnology involves engineering materials and devices on the nanoscale (1-100 nm) and can be applied to diagnostic pathology. It allows for early disease detection by taking advantage of nanoparticles' high surface area and ability to interact with biomolecules. Common nanodiagnostic techniques include magnetic nanoparticles for MRI contrast, nanochips for DNA analysis, microfluidics to automate biochemical assays, and nanoarrays for high-throughput screening of proteins and nucleic acids. Future applications may integrate multiple functions like imaging, detection, targeted drug delivery, and treatment monitoring into single nanodevices.