Public interest law does not describe a body of law or a legal field; the term was adopted to describe whom the public interest lawyers were representing, rather than what matters they would work on. Instead of representing powerful economic interests, they chose to be advocates for otherwise underrepresented individuals. Consequently, a significant current in public interest lawyering has always emphasized the need to provide legal services to those living in poverty. The impact factor of journal provides quantitative assessment tool for grading, evaluating, sorting and comparing journals of similar kind. It reflects the average number of citations to recent articles published in science and social science journals in a particular year or period, and is frequently used as a proxy for the relative importance of a journal within its field. It is first devised by Eugene Garfield, the founder of the Institute for Scientific Information. The impact factor of a journal is evaluated by dividing the number of current year citations to the source items published in that journal during the previous two years.