What data types does BSON support?

BSON supports an extended set of types compared to JSON. The main ones are:

#The basic types

• Double, a floating-point number
• String, a string (UTF-8)
• Boolean, a logical type (true/false)
• Int32, Int64, integers
• Decimal128, an exact decimal number (e.g. for money)
• Null, an empty value
• Array, an array
• Object, a nested document

#The types unique to BSON

• ObjectId, a unique document identifier (12 bytes)
• Date, a date and time
• Timestamp, a type used for replication and internal operations
• Binary, binary data (e.g. files)
• Regular Expression, regular expressions
• JavaScript, JS code as a value
• JavaScript (with scope), JS code plus context
• Symbol, a deprecated type similar to a string
• MinKey and MaxKey, internal values used for sorting
• Undefined, a deprecated type, equivalent to undefined

Summary: BSON supports both ordinary data types (numbers, strings, arrays) and special ones, ObjectId, Date, Binary, Timestamp, and others, which help MongoDB work more efficiently than it would with plain JSON.