There are various reasons why a person would want to change his or her name:
In England and Wales, such a deed may be registered in the Central Office of the High Court. Deeds so registered are advertised in the London Gazette. A deed of name change on behalf of a minor must be approved by the Senior Master on behalf of the Master of the Rolls who will take into account the child's best interests. Registration of deeds is regulated by the Enrollment of Deeds (Change of Name) Regulations 1994, Statutory Instrument 1994 No. 604. Compared to some other European countries, e.g. Germany, a name change in the UK is easy and virtually unrestricted regarding choice.
The registration of a deed of change of name is not strictly required in the United Kingdom. A standard legal document, with stock wording, filled in by the person making the deed poll, and signed in presence of a witness, carries sufficient legal authority to be recognized. The witness need not be a solicitor but can be anyone over the age of 18 provided one is independent of the person changing one's name. Organisations such as banks, government departments, social security offices, etc., will not recognize a change of name unless presented with such a deed.
In the UK, a deed of change of name will not change the name on the person's certificate of birth. For instance, when applying for a passport, both the certificate and the deed would need to be presented as documents of identity.
In re Parrott, Cox v Parrott  Ch 183, Justice Harry Vaisey stated that he did not believe that a deed poll could be used to change a person's Christian name (first name)--that could be done by only an Act of Parliament. Deeds that change a person's first name are registered in the High Court, and they are usually endorsed "Notwithstanding the decision of Mr Justice Vaisey in re Parrott, Cox v Parrott, the applicant wishes the enrolment to proceed".