NBT

NBT is an acronym used in multiple disciplines. In computing, it most often denotes Named Binary Tag, a flexible binary data format used to serialize structured data. In biochemistry and immunology, it commonly refers to the nitroblue tetrazolium assay, a colorimetric test that detects reactive oxygen species.

Named Binary Tag is a tag-based, hierarchical binary format designed to store small to large datasets efficiently. Data are organized as typed tags, including primitive types (byte, short, int, long, float, double) and reference types (string, binary data, list, and compound). Tags are identified by a type field and a name, enabling nested structures such as compounds (maps) and lists. The format is designed for fast parsing and compact storage and is used to serialize game state, world data, and other structured information in certain software, most famously the Minecraft game, where level files and entity data are stored as NBT.

The nitroblue tetrazolium assay measures the production of reactive oxygen species by phagocytes or other cells. In the presence of superoxide, nitroblue tetrazolium is reduced to blue insoluble formazan, forming crystals within cells or in solution, depending on the protocol. The amount of blue coloration correlates with ROS production and is quantified by microscopy or spectrophotometry. The assay has applications in immunology, microbiology, and plant biology, but results can be influenced by cell viability and other reducing agents.

Because NBT has multiple meanings, the intended interpretation hinges on the field of application.