17.1. Standard Containers

The standard library defines two kinds of containers: sequences and associative containers. The sequences are all much like vector (§16.3). Except where otherwise stated, the member types and functions mentioned for vector can also be used for any other container and produce the same effect. In addition, associative containers provide element access based on keys (§3.7.4).

Built-in arrays (§5.2), strings (Chapter 20), valarrays (§22.4), and bitsets (§17.5.3) hold elements and can therefore be considered containers. However, these types are not fully-developed standard containers. If they were, that would interfere with their primary purpose. For example, a built-in array cannot both hold its own size and remain layout-compatible with C arrays.