|The importance of antibiotics to medicine has led to much research into their discovery and production. Microorganisms used in fermentation are rarely identical to the wild type. This is because species are often genetically modified to produce the maximum amount of antibiotics. A journal is a periodical publication intended to further progress of science, usually by reporting new research. Most journals are highly specialized, although some of the oldest journals publish articles, reviews, editorials, short communications, letters, and scientific papers across a wide range of scientific fields. Journals contain articles that peer reviewed, in an attempt to ensure that articles meet the journal's standards of quality, and scientific validity. Each such journal article becomes part of the permanent scientific record.