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This dissertation describes two aspects of solar coronal dynamics: waves in coronal loops (Part I) and coronal mass ejections (Part II). The central theme is the development of new techniques used to extract crucial information out of the observations. We investigate the influence of (semi-) automated techniques on solar coronal research. This is a timely discussion since the observation of solar phenomena is transitioning from manual detection to `Solar Image Processing'. Our results are mainly based on images from the Extreme UV Imaging Telescope (EIT) and the Large Angle and Spectrometric Coronagraph (LASCO), two instruments onboard the satellite SOHO (Solar and Heliospheric Observatory) of which we recently celebrated its 11th anniversary. The high quality of the images together with the long timespan created a valuable database for solar physics research. Part I reports on the first detection of slow magnetoacoustic waves in coronal loops observed in high cadence image sequences simultaneously produced by EIT and TRACE (Transition Region And Coronal Explorer). These two instruments observe the hot corona in extreme UV emission lines. TRACE achieved a 25 sec image cadence in the Fe ix (17.1 nm) bandpass while EIT achieved a 15 sec cadence in the Fe xii (19.5 nm) bandpass. These multi-wavelength observations have revealed the existence of weak transients in extended coronal loop systems. The disturbances originate from small scale brightenings at the footpoints of the loops and propagate along the loops. By explaining the difference of the measured speeds with the sound speed as a projection effect we suggest that these weak transients are magnetoacoustic waves. The appearance of waves traveling at different speeds in the same loop, possibly suggests that these loops have sharp temperature gradients. Part II addresses the question of detecting coronal mass ejections in coronagraphic white light data. Coronal mass ejections (CMEs) are sudden expulsions of mass and magnetic field from the solar corona into the interplanetary medium. A classical CME carries away some 10 23 to 10 * * * *