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This animation clarifies how the Sun appears to move through the constellations of various background stars over the course of a year, the zodiacal constellations. The real Sun is projected by an observer on Earth onto the background stars, thereby ending up in the zodiacal constellations. The correct thirteen zodiacal constellations are shown. Move the Earth to thereby move the Sun's projection through its "orbit". Notice that the Earth advances in its orbit counterclockwise, as viewed from above (north) of the plane of the Earth's orbit (the Ecliptic Plane).
Use your mouse to hover over various parts of the animation. See if you can find the following items: the Ecliptic Plane, the Ecliptic, the Zodiacal Constellations, and the Zodiac. To find the Zodiac, place your cursor below the dotted line (the Ecliptic), and to the left of the Constellation Aquarius.
The Zodiac is not the same as the Zodiacal Constellations: the Zodiac is a region of space 8 degrees above and 8 degrees below the Ecliptic. The Zodiac is defined as that part of space where the orbits of the Sun, the Moon, and the principal planets reside.
Note that the Ecliptic Plane is defined as the plane in which the Earth's orbit resides. The fictitious (but useful) orbit of the Sun around the Earth, the Ecliptic, also resides in the Ecliptic Plane.
We can't actually see which of the "fixed" stars are behind the Sun: the Sun is blindingly bright, and Earth's atmosphere is colored blue by scattered sunlight. Nevertheless, we know, for today, which stars were over our meridian at midnight six months ago, so these stars would be the Sun's background stars at local noon today.
Given that the Earth goes around the Sun once per tropical year, it can be confusing to think about the Sun "orbiting" the Earth.
From a geocentric perspective, we say that the Sun appears to orbit the Earth once per year, following an orbit called the Ecliptic. The "orbit" is the path that the Sun appears to take in reference to the "fixed" stars as a backdrop. The plane in which the Earth's actual orbit around the Sun resides is called the Ecliptic Plane.
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