The document discusses selection as the most important function of HR to ensure the right candidate is hired. It notes it is better to not select than select the wrong candidate. The objective of selection is to choose the most suitable candidate. There are two basic testing concepts - reliability, which is consistency of measurement, and validity, which is the extent to which a test measures what it claims to measure. The selection process involves preliminary interviews, selection tests, employment interviews, reference and background checks, a selection decision, physical examinations, a job offer, and contract of employment.