First, a quick refresher course on what weaving actually is. Weaving is the process that creates fabric by interlacing yarn at right angles. The yarn in the vertical direction is called the warp, and the yarn in the horizontal direction is called the weft.
The crucial difference between a Jacquard and dobby loom is how the long, vertical warp yarns are moved up and down while the horizontal weft yarn is passed through. The process of moving different warp yarns up and down while the weft yarn is passed back and forth creates a pattern.
You can see in the photo above that the orange is the weft and the tan is the warp. By lifting half of the tan warp yarns up when the orange weft is passed through them, and then lifting the other tan yarns as it passes back, it creates a pattern.