| English | Spanish |
| International System of Units | Sistema internacional de unidades (The international metric system of units of measurement) |
| system of units | sistema de unidades (A set of units used for measurement or exchange) |
| username (The name by which a user is identified to a computer system or network. During the logon process, the user must enter the username and the correct password. If the system or network is connected to the Internet, the username generally corresponds to the leftmost part of the user's e-mail address (the portion preceding the | nombre de usuario |