Socialism is a way of organizing a society where major industries are owned and they are controlled by the government instead of individual people and companies. It is an economic and political system based on public or collective ownership of the means of production. Socialism emphasizes equality rather than achievement. Review articles are a summary of the current state of understanding on a particular research topic. They analyze or discuss research previously published by scientists and academicians rather than reporting novel research results. Review article comes in the form of systematic reviews and literature reviews and are a form of secondary literature. Systematic reviews determine an objective list of criteria, and find all previously published original research papers that meet the criteria. They then compare the results presented in these papers. Literature reviews, by contrast, provide a summary of what the authors believe are the best and most relevant prior publications. The concept of "review article" is separate from the concept of peer-reviewed literature. It is possible for a review to be peer-reviewed, and it is possible for a review to be non-peer-reviewed.