The first of the laws states that all planets in our solar system move in elliptical orbits with the sun at one of the points of focus of the ellipse. That is not surprising, perhaps as many of us have grown up knowing that the Earth's orbit and indeed the orbits of all the planets are elliptical.
An ellipse is essentially a squashed circle and you can imagine how it might have two points of focus if you first visualize a circle with a point at its center. If you were to squash the circle from top and bottom, the central dot would split in two and both would move outward. In the case of the planets in the solar system; the sun is found at one of these points and it is that point that they all appear to orbit.
ANALYSIS: Will Mystery Anomaly Mess With Today's Juno Flyby?
Kepler's second law states that a line joining the sun to a planet, known as the radius vector, sweeps out equal areas of space over equal time intervals. Put another way, planets move faster when they are closer to the sun and slower when further away. But it is Kepler's third and final law that was only published ten years after the first two which describes the mathematical relationship between the time it takes for a planet to complete an orbit and its distance from the sun. In the words of Kepler, "...the square of the orbital period of a planet is directly proportional to the cube of its mean distance from the sun." This means that we can measure how long an object takes to orbit the sun from simple observation and by knowing that, we can calculate its average distance with some accuracy.