In Schoolrunner, a "term" defines the beginning and end of the school year, usually from the fall through the spring of the next year. It's what you generally think of when you hear the phrase "school year". Schoolrunner needs a term with start and end date to operate.
A "term bin" is a span of time within the term. Generally, term bins reflect grading periods like quarters, trimesters, or semesters (see here if you want to add different types of term bins). To generate grades, Schoolrunner first needs term bins to be set up.
Students often get a grade that reflects their progress over the entire school term. For this, you'll need a term bin that has the same start and end date as your school term. Call this a "term-length term bin". Learn more about defining and managing term bins here.
Term bins are what you commonly see throughout Schoolrunner in menus and filters and date sliders, as shortcuts for filtering your data. Because of this, it's recommended to always create a term-length term bin, even if you only report out Q1-Q4 grades at the end of the year.