Grout sealer is a protective substance used to prevent moisture, stains, and contaminants from penetrating and damaging grout lines. It is essential for maintaining the appearance and longevity of tiled surfaces like bathroom walls, kitchen backsplashes, and floors. There are two types of grout sealers: penetration/impregnating sealers, which absorb into porous grout, and surface sealers, which create a protective layer on the surface. Grout sealers offer several benefits, including stain prevention, moisture resistance, easier cleaning, and extended lifespan. To apply grout sealer, clean the grout, choose the right sealer, ventilate the area, apply the sealer, wipe off excess sealer, and allow it to cure. Regular reapplying is recommended to maintain its effectiveness. Epoxy grouts may not require sealing, so check manufacturer recommendations.