I learned that
A connected graph has an Eulerian path if and only if it has at most two vertices of odd degree.
However, because of the term "at most", I'm very confused. What if a graph has $0$ vertices of odd degree, which satisfies "at most". Then does the graph have an Eulerian path?
I thought that a connected graph with $0$ vertices of odd degree has a Eulerian circuit.
Does "Eulerian path" include "Eulerian circuit"? Aren't the definitions of path and circuit definitely differently?