Answer by
LeheckaG (1826)
A "Working holiday visa" or "Working holiday maker visa" is a travel-permit allowing temporary immigration & temporary employment for the purpose of supplementing the applicant's travel-funds.
They are issued by certain countries with reciprocal agreements accepting other such visas;
and they often have restrictions on:
the traveler's age,
length of stay,
type of employment,
funds required while seeking employment,
...