The chronological CV is named thus as it details your career history most commonly in reverse chronological order with the most recent employment detailed first and working backwards. A complete record of career history is detailed along with a complete education record. It is the most frequently used CV and is usually 2 sides of A4 in length.
Job Titles and company names are emphasised with skills, duties and achievements detailed under each job title. A chronological CV is most useful if you are staying within the same industry and wish to show career progression.
Most employers prefer the chronological CV formats, as it is easy to see who you have worked for and what you did in each particular job. If you do not have many achievements you can take the emphasis off this fact when using a Chronological CV.
If you are changing direction and the most recent employer is not relevant to your new chosen career.
If your career history shows gaps in your employment due to poor health, unemployment, having children etc or that you have changed jobs frequently.