Q. what is peer review, and what is full text? Is everything full text?

Peer reviewed articles are submitted by the author, and then they are reviewed by 2 or more people who are considered to be experts in the field. Those experts decide if the information in the article add to the "body of knowledge" for that field.  If they decide it does then it may get published. If they decide it does not, then it won't get published in that journal. This type of review is a higher standard than simply editing an article to fit a particular journal.

Full text means the complete article is available, not just a summary.