Sisvar is a statistical analysis system first released in 1996, though its development began in 1994. Initially developed in Pascal and compiled with Borland Turbo Pascal 3.0, it was created to meet specific goals, including providing a reliable and user-friendly statistical analysis tool for Brazilian researchers. The system was designed to be free and accessible, addressing the limitations of existing software. Sisvar has gained widespread acceptance due to its reliability, accuracy, precision, simplicity, and robustness, as well as its high level of user interactivity. The system allows for the analysis of variance (ANOVA), regression, hypothesis testing, and multiple comparisons. It can handle various statistical models, including those with hierarchical and crossed effects. Sisvar's ability to slice interactions and nested effects, and to perform the Scott-Knott test, sets it apart from many competitors. It also supports a wide range of statistical analyses, including descriptive statistics, hypothesis testing, interval estimation, normality tests, and model selection methods. A new version of Sisvar in Java is under development to enhance its interactivity and compatibility with modern databases. This version will be cross-platform, running on Windows, Solaris, Mac OS X, and Unix/Linux. The Java version will use the db4o database, which is efficient and requires no installation. It will also provide source code and allow for community contributions, making it a collaborative effort. Sisvar is currently used in educational and research institutions across Brazil and is available for free download. The system continues to evolve, with ongoing updates and improvements. The development of Sisvar reflects a commitment to providing accessible, reliable, and powerful statistical analysis tools for the Brazilian scientific community.Sisvar is a statistical analysis system first released in 1996, though its development began in 1994. Initially developed in Pascal and compiled with Borland Turbo Pascal 3.0, it was created to meet specific goals, including providing a reliable and user-friendly statistical analysis tool for Brazilian researchers. The system was designed to be free and accessible, addressing the limitations of existing software. Sisvar has gained widespread acceptance due to its reliability, accuracy, precision, simplicity, and robustness, as well as its high level of user interactivity. The system allows for the analysis of variance (ANOVA), regression, hypothesis testing, and multiple comparisons. It can handle various statistical models, including those with hierarchical and crossed effects. Sisvar's ability to slice interactions and nested effects, and to perform the Scott-Knott test, sets it apart from many competitors. It also supports a wide range of statistical analyses, including descriptive statistics, hypothesis testing, interval estimation, normality tests, and model selection methods. A new version of Sisvar in Java is under development to enhance its interactivity and compatibility with modern databases. This version will be cross-platform, running on Windows, Solaris, Mac OS X, and Unix/Linux. The Java version will use the db4o database, which is efficient and requires no installation. It will also provide source code and allow for community contributions, making it a collaborative effort. Sisvar is currently used in educational and research institutions across Brazil and is available for free download. The system continues to evolve, with ongoing updates and improvements. The development of Sisvar reflects a commitment to providing accessible, reliable, and powerful statistical analysis tools for the Brazilian scientific community.