One of the roads is well-traveled, and the other is overgrown.
In this poem, a road diverges in a wood into two roads. Basically, the narrator finds himself at a fork in the road. He has to decide which one to take, because he can’t take both.
Then took the other, as just as fair,
And having perhaps the better claim
Because it was grassy and wanted wear,
Though as for that the passing there
Had worn them really about the same….
One of the roads is worn down, and the other is grassy. Metaphorically, one is the direction most people take, and the other is lesson common. The speaker decides to take the road less traveled, and he says that has made a difference. What that means is up to you. To some people, it means individualism is important. To others, it means there are choices in life.