With thousands of journals being published each year, a library cannot subscribe to them all. As a result, only selected journals are actually purchased and kept within the library building. The journals that a library subscribes to are OWNED by the library and anyone can go to the shelves and actually find the title and issue needed. They can physically touch the journal. This is OWNERSHIP.
To further aid the research needs of people who desire articles from journals that a library does not subscribe to, libraries try to provide ACCESS to the articles. There are two ways a library can provide access-- through full-text databases or through Interlibrary Loans.
By searching a full-text database, people can read/access articles to journals they need. Many times it is actually less expensive for a library to provide ACCESS to a journal then to physically OWN it.
By requesting an Interlibrary Loan, an article from a journal that the library does not OWN nor have ACCESS to, can be ordered from another library that does OWN the journal. A copy of the article is made and sent to the requesting library. The person who requested the article can come by the library and pick up the article.