Advocates have rights of audience in most of the courts. An advocate's role is to give advice on all matters of law: it may involve representing a client in the civil and criminal courts or advising a client on matters such as matrimonial and family law, trusts and estates, regulatory matters, property transactions and commercial and business law.
A barrister is a type of lawyer in common law jurisdictions with a split legal profession. Barristers specialise in courtroom advocacy and litigation. Their tasks include taking cases in large tribunals, drafting legal pleadings and giving expert legal opinions.
A solicitor is a legal practitioner who traditionally deals with any legal matter in some jurisdictions. A solicitor vary from one jurisdiction to another, to be described as a solicitor and enabled to practise in that jurisdiction.