Most paint thinners contain aliphatic hydrocarbons, dimethyl ketone, turpentine, methyl ethyl ketone, glycol ethers, xylene and ethylbenzene. However, different kinds of paint thinners have different chemical compositions.
The substances commonly referred to as paint thinners are used to thin or remove oil-based paints, though the name has come to also include solvents used for latex-based paints as well. They tend to be highly toxic and should not be used in an enclosed environment. Most are highly flammable and also should not be used or stored near an open flame.