Makeup sponges, such as the popular "beauty blender" type, are typically reusable. They are made of a porous, expandable material that can be used to apply makeup, and then washed and reused.
To clean a makeup sponge, you can use a mild soap or a makeup brush cleaner, and then rinse it thoroughly with water. You can then squeeze out the excess water and let it air dry. It's important to clean your makeup sponge regularly to avoid the buildup of bacteria or makeup residue.
It's also worth noting that some makeup sponges have disposable versions, which are typically made of foam or cellulose, and meant for single use, these are usually cheaper than reusable ones.
In addition, some makeup sponges are made of silicone, those are also reusable and easy to clean, but they are not as good at blending the makeup as the traditional sponge.