A database is usually a "large collection of data organized especially for rapid search and retrieval (as by a computer)." [From "Database.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/database.]
You are already familiar with many databases. For example, you are using a database when you search for a specific course or browse your course options in Chemeketa's online course schedule. NetFlix, Hulu, and Amazon Prime Video are searchable databases of streaming video available to subscribers. If you use contacts on a smartphone, that's a database of names, numbers, and addresses that you have collected. All three of these examples are searchable collections of data.
Library databases are searchable collections of data, too. Most Chemeketa Community College library databases are used to find books, articles, video and images in online and on-the-shelf formats. Some have specialized content, such as automotive repair guides (ChiltonLibrary.com).
Most library databases are not available freely on the web. Libraries pay for access to databases. Access to databases through your library is one of the services you pay for as a student. Most libraries have online databases but they don't all have the same databases. You must be a student at a college or university to have online access to the databases it subscribes to.
All Chemeketa Community College library databases are available at
PowerSearch is not a database. It is a tool that searches many databases at the same time. It does not search in all library databases.
This video briefly and clearly explains what a journal article is and why we use library databases to find journal articles on a topic.