• Data reference period
• Place of residence (Portugal)
• Sex
• Type of activities performed at computer

• REFERENCE PERIOD:  The length of time for which data are collected, e.g. a specific day, month or year.
• PERSONAL COMPUTER:  Personal use system with own processing and communication capabilities: Desktop and Tower' geared to run general use applications; Workstations' geared to process applications with significant processing and graphical demands; Laptops' geared to run general use applications, characterised by its reduced dimensions and weight, with an autonomous electrical feed; Terminals 'input/output units without own processing capabilities, via which a user communicates with the computer.
• RESIDENT POPULATION:  Set of persons who, regardless of being present or absent in a given housing unit at the moment of observation, have lived in the place of their usual residence for a continuous period of 12 months prior to the moment of observation, or have arrived to the place of their usual residence during the period of 12 months prior to the moment of observation, with the purpose of living there for a year, at least.

(Persons aged between 16 and 74 years old performing computer related activities/ Resident population aged between 16 and 74 years old)*100