 UV mapping and unwrapping is the process of skinning your 3D object onto a 2D surface for texturing. If you want your image textures to properly project onto your mesh, this process is very important. But what does a UV map actually look like? What does it do? Well, let's go ahead and show you. Simply select your object and go into edit mode. Select your entire mesh by pressing A. Then go to your image editor and change it to the UV editor in the top left hand corner. This is basically the same thing as your image editor, but we'll display your selection's current UV map over any image you choose for reference. It's also got a few extra settings specifically for UV editing. Alternatively, you can also go to the UV editing workspace, which will bring you to the UV editor automatically. As you can see, our default cube already comes unwrapped, as do most of our primitive meshes. This is the UV map of our cube. So instead of explaining it to you, I'm going to demonstrate how UV mapping works with an image texture. All I'm going to do is navigate to a file in my file browser and drag it to my shader editor as an image texture node. You can see that our UV editor automatically displays the image from our image texture node we have selected in the shader editor. But then, why is our cube still white? Well, to actually apply this image to our shader, simply click and drag the color output into the base color input of our shader node. If your texture isn't showing up, make sure you're in look dev or rendered mode in the viewport. To understand UVs, let's go into the UV editor and select some faces. You can choose a selection mode in the UV editor just like you can in edit mode in the viewport. This will allow you to edit the UVs like you would a mesh. GS and R hotkeys also work the same as usual. However, we also have some extra tools in the toolbar. To transform without hotkeys, simply select the transform tool. As you drag things around in the UV editor, you'll notice our image is distorting a little bit on the cube. For example, we can see that this square here is correlated with this square on the cube if we simply move it around a bit. We can also scale everything up to repeat the texture across the mesh. It's important to note that by default, the UV editor will only show the vertices, edges, and faces you have selected in the 3D viewport. This also helps make it clear which face in the 3D viewport correlates to which face in the UV editor. For example, we can go into face select mode in the viewport and select the face. That will isolate the corresponding UV face in the UV editor. However, you can also flip this function and have the UV editor drive what face you have selected in the viewport. To do that, simply click this opposing arrows icon on the very top left of the UV editor. Keep in mind, if you don't see all the buttons here, you can expand the UV editor or scroll along the top bar. With this mode toggled, we can now go into face select mode in the UV editor and select faces in our UV map, which will then select only the corresponding face in the viewport. Which function you want to use is up to you. I typically work with the default function as it keeps my UV editor clean. Now that we understand the UV editor and have an image projected onto our cube, let's go and take a look at the different unwrapping algorithms we can use. Unwrapping refers to the process of taking a 3D mesh, unravelling its faces and lying them out on a 2D surface. To begin unwrapping, simply go up here to the UV menu or press U. Even though our cube is already unwrapped, these are different unwrapped algorithms that we can use. Unwrap is your standard unwrap algorithm. This simply takes into account what seems you have marked, which we'll get into in a little bit, and unwraps your mesh accordingly. Smart UV project is one of my favorites and is great for unwrapping things quickly and roughly. Lightmap and follow-active quads are similar, but have their own algorithms. Cube, cylinder, and sphere projection are algorithms most fitted for objects similar in shape to the name of the algorithm. Project from view is a very powerful tool that essentially takes what you see in the viewport and flattens it as your UV map. This is a very basic way of unwrapping your mesh and will not hold up from different perspectives, but can be used selectively to great effect. Project from view bounds simply stretches the resulting UV across the UV editor. I'm going to demonstrate this one real quick, so let's go ahead and select project from view. As you can see, the image projects pretty well on our cube from this perspective. However, if we rotate our perspective, you can see that the image is now stretched across the sides that are perpendicular to our view from before. That's because, as you can see in our UV editor, there are not enough pixels for those faces in the UV map. Now, you may have noticed that we can't get the original mapping of our cube back. Pressing the unwrap option doesn't seem to do anything because our cube is already unwrapped. So let's go over exactly how to use the basic unwrapped function. To do this, we need to mark some seams. Seams are the edge loops where you specify for blender to cut open your mesh when skinning it. Simply select the edge loops you wish to mark or clear before clicking each option. So let's go into edge select mode and select these three edges. I'm going to do the same thing on the other side of the cube. Then I can click mark seam in our unwrapped menu to mark these edges as where we want to cut open the mesh. This will make them appear slightly redder. Then I'm going to go ahead and select this edge as well and do the same thing. Now I can select all of my mesh and go to the unwrap menu and select unwrap. As you can see, we have something more similar to what we had before. In case you don't understand why I chose the seams that I chose, let me walk you through my thought process. The arms of the cross we see in the UV map are these faces here. They needed to completely detach except for one connected edge, so I marked seams on the three other edges of each of these faces. Then we simply needed to separate the head of the cross from the tail of the cross. That's what this seam was for. As you work with your own meshes, you'll get a feel for what seems to work best for you to get the UV map shape you want.