A solar burst is a suddenly enhanced nonthermal radio emission from the high solar corona immediately following a solar flare, probably due to energetic electrons trapped in the coronal magnetic field. Bursts are divided into several types, depending on their time frequency characteristics (type III is the most common). They are classified on a scale of importance ranging from -1 (least important) to +3. Bursts are generally attributed to a sudden acceleration of some 10³⁵ to 10³⁶ electrons to energies greater than 100 keV in less than one second.