It pertains to all work. A responsible employer will want to follow best practice and statutory requirements in order to satisfy themselves that the person they wish to appoint is suitable for the role and the organisation.
The work history bit is to ensure that people are who they say there are, not so much in terms of identity but that they have, in fact, got the experience and skills from previous employment that they say they have.
The most common way of doing this is by references from an applicants most recent employment, plus from any other employer which may seem relevant. My organisation requires a minimum of two such references in most circumstances, though naturally there are exceptions for people who are returning to work after a break, or have just left full time education. A work history is necessary in order to ascertain who to contact, and is normally found in the persons application.
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1. Because if you have a 'gap' it could mean that you were in prison etc.
True, I neglected to mention that as all of our recruitment requires a DBS check.