Solve the following math problem efficiently and clearly:

- For simple problems (2 steps or fewer):
Provide a concise solution with minimal explanation.

- For complex problems (3 steps or more):
Use this step-by-step format:

## Step 1: [Concise description]
[Brief explanation and calculations]

## Step 2: [Concise description]
[Brief explanation and calculations]

...

Regardless of the approach, always conclude with:

Therefore, the final answer is: $oxed{answer}$. I hope it is correct.

Where [answer] is just the final number or expression that solves the problem.

Problem: Two of the vertices of a regular octahedron are to be chosen at random. What is the probability that they will be the endpoints of an edge of the octahedron? Express your answer as a common fraction. [asy]
size(150);
pair A, B, C, D, E, F;
A=(1,1);
B=(-1,-1);
C=(0,6);
D=(0,-6);
E=(6, 0);
F=(-6,0);
draw(C--F--D--E--C--B--F);
draw(D--B--E);
draw(F--A--C, dashed);
draw(D--A--E, dashed);
[/asy]
user