Who is a Barrister and what do they do?

A Barrister is a lawyer with the right to speak and argue as an advocate in higher lawcourts. Barristers are instructed by solicitors. They specialise in a particular field of law and can present a case in any court, where as a solicitor's rights to speak in court are limited.
Another term for Barrister is 'Counsel'.
Barristers normally have no direct contact with the public and appear in court when instructed to do so by a solicitor.
Barristers put legal arguments to judges, magistrates and juries, and they cross-examine witnesses to attempt to control the outcome of a court case.
Only barristers or qualified Solicitor Advocates may represent clients in the higher courts.