Drywall texturing is indeed a fantastic way to enhance the visual appeal of your walls and ceilings while also masking minor imperfections. Here's a brief overview of the texturing techniques you mentioned:

1. Comb Texture: This technique involves using a notched trowel or a special comb tool to create patterns of lines in the drywall compound. The lines can be straight, curved, or in various geometric patterns, depending on the desired effect.
2. Popcorn Texture: Often used on ceilings, this texture involves spraying a mixture of drywall compound and Styrofoam or other materials to create a bumpy, popcorn-like surface. It's great for hiding imperfections and providing some sound insulation.
3. Orange Peel Texture: This texture resembles the surface of an orange peel. It's achieved by spraying a thin layer of drywall compound onto the surface and then letting it dry. The result is a subtle, bumpy texture that's more refined than popcorn.
4. Knockdown Texture: This technique starts with spraying a texture (similar to orange peel) onto the wall or ceiling. While the compound is still wet, a trowel or knife is used to "knock down" the peaks, creating a flattened, mottled appearance.
5. Sand Swirl Texture: This involves applying a thin layer of joint compound mixed with sand, then using a brush or trowel to create swirling patterns. The sand adds a gritty texture, making it both visually and tactilely interesting.
6. Slap Brush Texture: This technique uses a stiff-bristled brush to slap or dab the wet drywall compound, creating a series of small peaks and valleys. The result is a textured surface with a lot of depth and character.

Each of these techniques can be tailored to suit different aesthetic preferences and functional needs. Whether you want something subtle or more dramatic, there's a drywall texture to match your vision.