Time-resolved study of a system reveals the dynamics of a short lived entity, the excited state. A large number of events in nature take place on the time scales of nano, pico or femto seconds. Time-resolved spectroscopy therefore, is an interdisciplinary subject. The property associated with the ultrafast laser pulses is the high peak power confined within a short time interval. Combined with the nonlinear optics (a subject within the ultrafast laser optics), exotic phenomena such as harmonic generation can be achieved. Modern lasers have achieved the range of electromagnetic spectrum right from the millimetre waves (THz) to X-rays. Besides the visible and near infrared region, femtosecond coherent x-ray pulses are now available at large-scale facilities as well as on table-top systems. In this talk, this subject will be introduced along with a brief account of the activities at IIT Madras related to topics such as optical parametric amplification, whispering gallery modes and multiphoton spectroscopy.