Cover letters give an employer some idea of why you are applying for a job. They point out things in your CV which relate to the job such as your interests and skills. Find out what you should include in a cover letter.
CV's - Curriculum vitae
Your CV should be an account of your career. It should explain to an employer what you can do and what you have done. Make sure you find out what you should include and what you shouldn't in your CV.
A speculative letter can be used to write to employers asking if they have any vacancies. Some employers don't always advertise vacancies so you could be lucky by sending out a speculative letter. Find out more information on how to write a speculative letter.