The following terminology is used thoroughly within Xeres.

A profile is an abstract that defines a user of Xeres. It is backed internally by a PGP key. Ideally, you should only have one and use it on multiple devices.

Synonyms: friend

A profile can create one or several locations. A location is backed internally by an RSA key and a certificate. It is basically an instance running on a device which will network with other locations. They're signed by a profile and can also connect between each others within the same profile.

Examples: a location on your desktop machine and another on your laptop.

Synonyms: node, peer

And now to complicate matters...

A location can create one or several identities. An identity is internally backed by an RSA key. It is used by several services (chat, forums, ...) and everything using GxS (General Exchange Service). An identity is signed by a profile, otherwise it's an anonymous identity which can't be linked to any location or profile.

Synonyms: contact, people, person

A Xeres ID or Retroshare ID is a string that contains the necessary information for a connection to happen between two locations. After the exchange takes place, both locations can connect to each others.