It tells you what the ends of a particular graph do.
This could be written in different ways:
"Rises left, rises right" or "Falls left, rises right," etc.
Mathematically:
"As x --> -∞, f(x) --> ∞" or "As x --> ∞, f(x) --> -∞"
You need to understand both notations.
Let's put this in our commonplace journals for reference.
For each problem, identify the degree, the leading coefficient, and the end behavior.
When it's your turn:
Write a function (secretly) on the graphing calculator
Show the graph (but not the function) to everyone else
See if they can figure out whether the degree is even or odd and whether the leading coefficient is positive or negative.