Titanium is well known for its excellent resistance to corrosion; it is almost as resistant as platinum, being able to withstand attack by acids, moist chlorine gas, and by common salt solutions. Pure titanium is not soluble in water but is soluble in concentrated acids. A metallic element, it is also well-known for its high strength-to-weight ratio. It is a light, strong metal with low density that, when pure, is quite ductile (especially in an oxygen-free environment), easy to work, lustrous, and metallic-white in colour. The relatively high melting point of this element makes it useful as a refractory metal. Commercially pure grades of titanium have an ultimate tensile strength equal to that of high strength low alloy steels, but are 43% lighter. Titanium is 60% heavier than aluminium, but more than twice as strong as 6061-T6 aluminium alloy; these numbers can vary quite substantially due to different alloy compositions and processing variables.

 Titanium was first discovered in 1791 in Menachan Valley, Cornwall, England, by clergyman and amateur chemist William Gregor.  Gregor analyzed gun powder-like sand and found a reddish brown clay he could not identify.  Four years later in Berlin, renowned chemist Martin Heinrich Klaproth independently discovered the element in rutile. Klaproth named the element Titanium, after the mythological Titans, first sons of the earth.