A namespace is a context, within which the names are unique. Namespaces can be hierarchical, meaning the names within each hierarchical level are unique. Examples:

  • Soccer: Namespace is the team. The shirt number is the unique name within this.
  • Telephony: Namespace is the area code, the number of the connection is the unique name within this.
  • Domain Name System (DNS): Namespace is a second-level domain. Here, the hostnames (www) and the subdomains (dev) are unique.
  • URIs (Uniform Resource Identifiers): Each URI can be taken as a name with the parent resource as the namespace.