The New Jersey Plan and the Virginia Plan were both meant to settle the issue of representation in Congress during the creation of the new US Constitution.
The New Jersey Plan was meant to benefit the smaller states. In this plan, it called for a unicameral legislature in which all states would have one representative. The larger states disliked this idea, as they felt their population should have some bearing on how many representatives they have.
This is why the Virginia Plan called for a bicameral legislature in which representation would be based on a states population. A larger population would equal more representation in Congress.