The two roads represent two different paths through life. At different points in our lives, we face different choices. Some are more conventional choices, and some are more daring.
For example, writer and pastor Dietrich Bonhoeffer, who was already in trouble in Nazi Germany for resisting attempts of the Nazis to redefine the Christian faith, arrived in New York in June, 1939, sponsored by friends who wanted to get him out of harm's way. The conventional path would have been to stay put, but a strong inner voice told he must go back to Germany and face that darkness, so he did. Like the speaker in Frost poem's, he took the road less travelled and never regretted the choice, even though he ended up imprisoned and killed.
Frost's traveller does have to choose which way to go. After studying his options, he picks the less travelled road—the one more overgrown with grass. He says the two paths were not that different but also that he never regretted taking the one he did. This choice suggests it can be rewarding to take even a slightly less conventional path in life.