All wood can be laser cut, the depth and speed of the cut will vary depending on the density of the wood. Softwoods like balsa are easier to cut than hardwoods like walnut. Be careful with woods that contain a lot of resin, as they are more likely to catch fire. Since wood is a natural material, the finish obtained will vary greatly. This is especially true when engraving. As there will be strips of wood of different densities, they will respond slightly differently to the laser, resulting in variable finishes. Other woods to consider are cherry, oak, spruce, bamboo, and pine.
Plywood is more difficult to cut than natural wood because of the adhesive used to hold the layers together. Formaldehyde may also be released when the laser beam reacts with these adhesives. So good ventilation is a must. Since the top surface of plywood is a natural material, you will have the same carving problems as solid wood. Plywood is also prone to warping if not stored properly. Difficult to process unless you can lay it flat under the laser head.
MDF is an engineered wood product held together with adhesives. It has the same problem as plywood, which may form formaldehyde gas. However, there are now some "laser-friendly" low-formaldehyde hybrid MDF boards on the market. Engraving on MDF is easier because it has a more consistent surface, although the results can be very bland. You also get MDF veneers with consistent cutting performance and an aesthetically pleasing finished finish.
Paper can be cut easily and quickly with a laser, but you need to make sure you don't use too much power as it will burn the edges. If you mix long clips and fine detail work, it's best to group each type of work and give them different settings. Fine detail work tends to run more slowly and require lower power settings than long cuts.
Museum cardboard is a white cardboard that bends easily in one direction but is stiff in the other due to the texture of the paper fibers. Since it's based on paper fibers, it's easy to cut with a laser.
Standard cardboard is cut in the same way as paper, just with a higher power setting to add thickness. Corrugated cardboard is more difficult because it tends to be relatively thick compared to standard cardboard. It also has an air gap that collects fumes during cutting. This smoke diffuses the laser beam, making it less effective. The usual response is to increase power or slow down. Both can cause the cardboard to catch fire. One solution (if available in your laser software) is to use the Dot function. This causes the laser to pulse, reducing the heat generated within the cardboard.
For the most part, cork cuts and carves well, but you may have difficulty cutting through thicker sections. If you're stuck, it might be worth trying dot mode.
Leather cuts easily and can be engraved with great success. Just be careful not to let debris fall back onto the engraving surface as it can be difficult to clean afterwards. However, the main downside is the smell! It is very pungent and can only be extracted in place.
Be careful not to process leather, which is sometimes called fake leather or imitation leather. Faux leather can contain PVC or polyurethane.
Be careful when handling chrome tanned leather as toxic chrome V1 may be released. It is best to stick vegetable tanned leather, which is safer.
You can cut and carve many food items. However, unless you have a dedicated laser with a sanitary surface, it's best to use food for display purposes rather than eating.