There are three common types of laundry sheets: detergent sheets (solid detergent strips for washing), dryer/fabric-softener sheets (for the dryer to reduce static and add softness), and color-catcher/dye-trapping sheets (to absorb loose dye in mixed-color loads).
Both. Many laundry-sheet products are sold in a variety of named scents, and several brands also offer unscented or “no fragrance added” formulations aimed at scent-sensitive users.
According to the product listings summarized here, detergent sheets are described as dissolving completely in both hot and cold water and are marketed as compatible with all washing machines, including front‑load and top‑load models.
Some product listings warn against using sheets on delicate or specialty materials—examples include velvet, suede, leather, wool, and rayon. Listings also sometimes recommend special handling (for instance, placing a dye‑trapping sheet in a delicates or mesh bag for front‑loading washers).
Several detergent‑sheet listings describe compact, travel‑friendly formats, and at least one explicitly notes leak‑proof or spill‑proof packaging and TSA compliance. Always check the specific product description and current TSA rules before travel.