a specific case instead of a class of cases. An in mitius change may alleviate possible consequences for unlawful acts (for example by replacing the death sentence with lifelong imprisonment) retroactively. Finally, when a previous law is repealed or otherwise nullified, it is no longer applicable to situations to which it had been, even if such situations arose before the law was voided; this principle is known as nullum crimen, nulla poena sine praevia lege poenali. Software development The term is also used in software engineering, where a retrospective is a meeting held by a project team at the end of a project or process (often after an iteration) to discuss what was successful about the project or time period covered by that retrospective, what could be improved, and how to incorporate the successes and improvements in future iterations or projects. Retrospective can be done in many different ways. In agile development, retrospectives play a very important role in iterative and incremental development. At the end of every iteration a retrospective is held to look for ways to improve the process for the next iteration. Standards In the context of scientific and technical standards, retrospectivity applies current norms to material that pre-dates new rules. An example of a retrospective or retroactive standard is the International Code of Zoological Nomenclature (ICZN Code), a convention which governs the formal scientific naming of animals, of which the 4th edition is effective since 2000. All previous editions of the ICZN Code, or previous other rules and conventions are disregarded today, and the scientific names published in former times are to be evaluated only under the present edition of the ICZN Code. See also After action report After-action review Debriefing Lessons learned Morbidity and mortality conference Performance appraisal References External links Film genres Visual arts exhibitions