Answer:
The main difference between a treaty and an executive agreement, is, that the treaty is a form of executive agreement that depends, for its enforcement and activation, to be accepted by a two-thirds vote in the Senate, while an executive agreement, by itself, is an agreement between countries where the decision of its acceptance does not depend on a vote on the part of the U.S Senate.
Step-by-step explanation:
A treaty is an agreement that is reached between different nations, but which depends on the acceptance by the U.S legislature, particularly the Senate, to be effective. However, an executive agreement, while still an agreement between nations, and having to be frameworked under the Constitution, does not need a two-thirds vote, or any vote for that matter, from the legislative branch, to come into force.