A power of attorney (POA) or letter of attorney in common law systems or mandate in civil law systems is an authorization to act on someone else's behalf in a legal or business matter. The person authorizing the other to act is the principal or granter (of the power), and the one authorized to act is the agent or attorney-in-fact HTH LOL
However, assuming that Blade1jet2 is in the UK and that he/she wants to know something about a lasting or enduring power of attorney, all of the information that he/she wants should be here: http://www.publicguardian.gov.uk/