What is Stain?
A '''stain''' is a spot that has another color than the material on which it is found. It can occur without [[intention]] in the case of domestic stains on [[textile|fabric]], [[cloth]], or other material, or it can be intentional. Stains are used intentionally in a variety of fields, including [[research]] ([[staining (biology)|biochemical staining]]), [[technology]] (metal staining), and [[art]] ([[wood staining]], [[stained glass]].) Different types of material can be stained by different substances, and [[#Stain resistance|stain resistance]] is an important characteristic in modern [[textile engineering]]. Various laundry techniques exist to attempt to remove or minimize existing stains, and [[#Stain removers|stain removers]] are an important type of chemical in [[laundry detergent]]s.<ref>{{Cite web|last=|first=|date=2020-03-12|title=Stain Protection. To protect or not protect, That is the question!|url=https://safehandscleaning.co.uk/should-you-get-your-carpet-stain-protected/|archive-url=|archive-date=|access-date=2020-10-10|website=Safe Hands Cleaning|language=en-GB}}</ref> Some stand-alone stain removers also exist. ==Substances that may create stains== * [[blood]] * [[chocolate]] * [[coffee]] * [[fruit]]s and their [[juice]]s, particularly [[orange juice]] * [[grass]] * [[Petroleum|grease]] * [[ink]] (notably [[permanent marker]]) * [[oil]] * [[sauces]] (particularly [[tomato]] based) * [[Soft drink|soda]] (particularly [[orange soda]]) * [[sweat]] * [[wine]] * [[table salt]] * [[talc]], [[Corn starch|cornstarch]] or [[chalk]] * [[borax]] * lemon juice or lemon ===Fabrics=== * [[carpet]]<ref>{{cite web |url=http://www.carpetcleaninginnewportbeach.com/carpet-cleaning/same-day-carpet-cleaning-newport-beach/ |title=Carpet Stain Cleaning |website= |publisher= |accessdate=5 February 2018}}</ref><ref>{{cite web | url=https://beverlyhillscarpetcleaning.com/ | title=Carpet Cleaning Beverly Hills | access-date=2020-03-28 | archive-date=2020-03-28 | archive-url=https://web.archive.org/web/20200328150533/http