"A systematic review attempts to collate all empirical evidence that fits pre-specified eligibility criteria to answer a specific research question. It uses explicit, systematic methods that are selected to minimize bias, thus providing reliable findings from which conclusions can be drawn and decisions made."
Liberati, et al., 2009. The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate health care interventions: explanation and elaboration. J Clin Epidemiol 2009; 62: e1-e34.
There are a wide variety of different types of reviews. For an excellent summary of 14 review types, see Grant MJ, Booth A. A typology of reviews: an analysis of 14 review types and associated methodologies. Health Info Libr J. 2009 Jun;26(2):91-108. PMID: 19490148.
Here are some common categories:
Narrative reviews: Broad perspective on topic, no specified search strategy, significant bias issues, may not evaluate quality of evidence
Systematic reviews: Comprehensive with minimized bias, based on specific question and criteria with a pre-planned protocol, evaluates quality of evidence
Scoping Reviews: An overview of the literature on a broader topic; often done to identify whether a systematic review is feasible or to identify the overall state of the literature. For detailed information on how to do a Scoping Review, check out the Joanna Briggs Institute Guidelines.