The Darwinism is a doctrine which adherents adhere to the ideas about evolution created by Charles Darwin. Also often the term "Darwinism" is used for designation of theory of evolution in general that is not absolutely true.
The Darwinism is the doctrine based on the main ideas of evolution created by Charles Darwin and also on their modern processing with reconsideration of some aspects presented in the synthetic theory of evolution. Theories of evolution of other authors (if those are not Darwin's followers and do not develop his idea) do not belong to Darwinism.
The foundation for Darwinism was laid by the great scientist Charles Darwin, having published the book "The Origin of Species by Natural Selection or Maintaining the Favoured Breeds in Fight for Life" in which stated the opinion concerning formation of new types. Nevertheless, the scientist was concerned by obvious gaps in the theory. For confirmation of theory of evolution there were not enough transitional forms. Also it was unclear why useful signs were not lost when crossing with the "not changed" individuals. The solution came after publication of works of Mendel in which laws of heredity were open.
The synthetic theory was created on the basis of the discoveries of Darwin and the information about the geneticist received in the 20th century. As a result the initial theory received the strong base founded on modern knowledge and became even more convincing to look. According to Darwinism, the main driving forces of evolution are the heredity and variability. The variability is understood as various mutations which inevitably arose in populations. Thanks to natural selection of an individual, the got new useful signs, descended them to the descendants, the mutations harming a look were discarded. Extensive populations evolved gradually, and the intermittence and sharp variability in view of small quantity of their individuals was characteristic of small types. The major role evolutions was also played by preadaptive mutations. These are potentially positive changes which collected in population and at sharp change of the habitat allowed a look to survive. There are also other evolutionary theories. For example, supporters of autogenesis assumed that changes of a look happen at the expense of internal aspiration of individuals to self-improvement. External factors at the same time do not make any impact. Lamarkizm claims that new signs appeared in populations thanks to regular exercises of certain individuals and transfer of results of these exercises by inheritance. Similar hypotheses, though are evolutionary, have no relation to Darwinism.