Nuclear Medicine imaging involves use of a dedicated computer for data acquisition, processing, data display and data quantification. Computers integral and crucial component of other parallel imaging modalities like radiology ultrasonography, computed tomography, magnetic resonance imaging, functio0nal MRI, MR spectroscopy, diffusion tractography, Virtual Endoscopy and recent advances in these have been described in detail. The 21st century has ushered the era of hybrid imaging devices- SPECT-CT, PET/CT, PET/MRI which combine anatomic, physiological and biochemical information to be obtained all at once. Unique, capabilities of each modality are described in detail including image guided interventions.