Editing Algorithmic efficiency (section)

====Theory====
[[Analysis of algorithms]], typically using concepts like [[time complexity]], can be used to get an estimate of the running time as a function of the size of the input data. The result is normally expressed using [[Big O notation]]. This is useful for comparing algorithms, especially when a large amount of data is to be processed. More detailed estimates are needed to compare algorithm performance when the amount of data is small, although this is likely to be of less importance. [[Parallel algorithm]]s may be [[Analysis of parallel algorithms|more difficult to analyze]].