|Bacteriology is the branch of microbiology, which deals with the study of bacteria. Bacteria are microscopic organisms which have spread in the environment and are the inhabitants of soil, water as well as human bodies. The study of bacterial structure, shape and physiology is called as bacteriology. Most of the bacteria appear in different shapes such as oval, coccal, spiral etc. High-impact journals are those considered to be highly influential in their respective fields. 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.