What is the difference between job analysis and job description?Also, please explain job design?

Job analysis is one of the preliminary activity necessary for preparing a proper job description. However job analysis may be used for other purposes also.

A job description is defined by BS 32207 as a written outline of the main tasks of a job. It is a written statement covering the essential features of a job, including its purpose, duties, skill requirements and a set of duties and responsibilities that indicate the content of the job in detail. One obvious use of job description is for clarifying duties and responsibilities. Other uses of job description include job evaluation and merit rating, and preparation of job specifications.

Job analysis is a systematic process of analyzing a job for identifying job contents, leading to job description, job specification, and job evaluation.It involves determination of the requirements of the job through detailed observation and evaluation of work performed, facilities required, conditions of work, and the qualifications required of the worker. BS defines job analysis as the determination of essential characteristics of a job in order to produce a job specification.

Job evaluation helps in design of jobs that enable achievement of organizational goals and objectives effectively and efficiently. It is also used to design jobs that lead to better involvement and job satisfaction for people who perform the jobs.