Commercial transactions carried out over the Internet with an aim to buying or selling products or services. From 2000 to 2002 this included purchases made for work reasons, however, from 2003 they were excluded. Orders are made over the Internet, while payment and delivery may be made online or by another means.

From 2000 to 2002 this included all Internet users who had bought something. From 2003 on it included those who had purchased over the last three months.

However, for the whole 2000 series onwards the Internet users who had ever bought online were included.