Primary data= data you collect yourself using methods such as
interviews, archival records, questionnaires, focus groups,
participatory observation, diaries. The key point here is that the
data you collect is unique to you and your research and, until you
publish, no one else has access to it.
Secondary data=Published data and the data collected in the past by
somebody else. This can be processed for scholarly audiences (articles
in professional journals) or not (internal organizational reports and
records, published statistics or policy papers, censuses, surveys).