A journal is a collection of academic articles that are published periodically throughout the year. This could be published on a monthly basis or every couple of months a year. It usually contains volumes and issues. For example, “Journal of Forestry” or “Journal of Psychology”.
An article (also known as journal articles, academic articles or scholarly articles) are shorter than books, and are published in journals. Academic articles are written by experts in the field for academics (such as students and professors) and researchers. These articles often have extensive citations/references at the end of each article.
Peer-reviewed articles are articles that have been reviewed by other experts in the field and are considered to be the best types of articles. You can determine if a journal article is peer-reviewed using UlrichsWeb.
Databases collect and organize many journals about a particular field of research together in a single place that can be searched easily. For example, "Sociological Abstracts" or "Anthropology Plus".
In other words, you search a database to find articles that have been published in journals.