The mini-AOD data format for the CMS experiment data analysis.
The CMS experiment has developed a light analysis object format called "Mini-AOD", which has been successfully used since 2015. The motivation for the Mini-AOD format is to have a small and quickly derived data format from which the majority of CMS analysis users can start their analysis work. This format is aimed at having sufficient information to serve about 50--80% of CMS analysis, while significantly simplifying the disk and I/O resources needed for analysis. Such large reductions were achieved using a number of techniques, including defining light-weight physics object candidate representations, increasing transverse momentum thresholds for storing physics object candidates, and reducing numerical precision when it is not required at the analysis level. Thanks to recent developments the mini-AOD usage will be increased, targeting up to 90% of CMS analysis. The main characteristics of Mini-AOD data format will be covered in this talk. In addition, the most recent features will be discussed.