What is the difference between a y-intersection and a t-intersection

I had to ask for help on this one. I had no idea what it meant. The people on the forum figured it out (I think). They said it was a driving question and I should have known. I live in the country. We have plenty of both.

Y intersection looks just like a Y. You are coming from the bottom of the Y and moving upwards. You come to a fork in the road and you must choose to go upwards either by taking the left or right hand side. Both will permit you to go in the same direction you were traveling in the first place. You might wind up in a slightly different place.

T intersection. A t Intersection makes you stop because you cannot keep going in the direction you were traveling in the first place. That direction is a complete Dead End. 

You are forced to go either left or right at the intersection. The original direction you were travelling is now lost to you. If you were travelling North then the T requires you to go either East or West.

If they have missed the question, let me know. I can edit it.

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