This report serves as a primer on class action litigation in the federal courts. It begins by discussing the purpose of class actions, as well as the risks class actions may pose to defendants, class members, and society at large. The report also discusses the prerequisites that a class action must satisfy before a court may "certify" it--that is, before a federal court may allow a case to proceed as a class action. An Appendix to the report also contains a reference chart that graphically illustrates those prerequisites for class certification. The report then discusses Rule 23's restrictions on the parties' ability to settle a certified class action. The report concludes by identifying ways in which Congress could modify the legal framework governing class actions if it were so inclined, with a particular focus on a bill currently pending in the 115th Congress that would effectuate a variety of changes to the class action system.