A database is software that manages data including storing, indexing and performing queries. Some are internal to an application, but many run as a service used by multiple applications, either running on a central computer or using some form of cloud service. The most common forms are relational databases (effectively collections of large, interconnected tables), which typically use the SQL query language, and noSQL databases, which use simple key-value bindings to JSON objects.
Used in Chap. 2: pages 16, 17, 18; Chap. 3: pages 25, 32, 33; Chap. 5: page 71; Chap. 10: page 132; Chap. 12: page 180; Chap. 13: pages 189, 193, 198, 200; Chap. 14: page 218; Chap. 16: page 238; Chap. 17: pages 251, 253, 254; Chap. 21: page 332; Chap. 22: page 344