A database is software that manages data inclduing 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) and noSQL databases, which use simple key-value bindings to JSON objects.
Used in Chap. 2: pages 16, 17; Chap. 3: pages 27, 34, 35; Chap. 5: page 78; Chap. 10: page 143; Chap. 12: page 195; Chap. 13: pages 204, 208, 213, 214, 216; Chap. 14: page 235; Chap. 16: page 256; Chap. 17: pages 269, 273, 274; Chap. 21: page 353; Chap. 22: page 366