In Photoshop, a layer is a single level in the images' stacking order that contains an individual element, such as an image, text, or shape. Layers allow you to work on specific parts of an image without affecting the rest of i. You can apply various effects, filters, and transformations to each layer independently, making it a powerful toll for image editing.
On the other hand, a layer group is a collection of one or more layers that can be grouped together for organizational purposes. You can think of it as a folder that contains multiple layers. By organizing your layers into groups, you can keep your workspace neat and tidy, and easily manage complex projects.
Layer groups also offer some additional features that individual layers do not. For example, you can apply layer effects to a group, which will be applied to all the layers inside the group. You can also apply blending modes and opacity to a layer group, which affects all the layers within it.
Overall, layers and layer groups are both essential tools in Photoshop tha allow you to work efficiently and effectively. While a layer is a fundamental building block of an image, a layer group helps tou orgnize your layers and apply effects and transormations to multiple layers at once.