What the law says:

""data" means information which —

(a) is being processed by means of equipment operating automatically in response to instructions given for that purpose,

(b) is recorded with the intention that it should be processed by means of such equipment,

(c) is recorded as part of a relevant filing system or with the intention that it should form part of a relevant filing system;

(d) does not fall within paragraph (a), (b) or (c) but forms part of an accessible record"; or

(e) does not fall within paragraph (a) to (d) but is recorded information held by a public authority.

What it means:

"Data" is information which is

"accessible record" is defined in section 62 of the Act and means

a health record,

an educational record,

a social work record; or 

information held by the Department of Infrastructure, a local authority or board, for any purpose of the relationship of landlord and tenant of a dwelling which subsists, has subsisted or may subsist between the authority and any individual who is, has been or, as the case may be, has applied to be, a tenant of the authority.