Nectarines

The nectarine cultivar group of peaches have a smooth skin. It is often referred to as a "shaved peach", "fuzzy-less peach" or "shaven peach" due to its lack of fuzz or short hairs. Though fuzzy peaches and nectarines are regarded commercially as different fruits, with nectarines often erroneously believed to be a crossbreed between peaches and plums, or a "peach with a plum skin", they belong to the same species as peaches. Several genetic studies have concluded nectarines are created due to a recessive allele, whereas a fuzzy peach skin is dominant. Nectarines have arisen many times from peach trees, often as bud sports.

As with peaches, nectarines can be white or yellow, and clingstone or freestone. On average, nectarines are slightly smaller and sweeter than peaches, but with much overlap. The lack of skin fuzz can make nectarine skins appear more reddish than those of peaches, contributing to the fruit's plum-like appearance. The lack of down on nectarines' skin also means their skin is more easily bruised than peaches.

The history of the nectarine is unclear; the first recorded mention in English is from 1616, but they had probably been grown much earlier within the native range of the peach in central and eastern Asia. Although one source states that Nectarines were introduced into the United States by David Fairchild of the Department of Agriculture in 1906; a number of colonial era newspaper articles make reference to nectarines being grown in the United States prior to the Revolutionary War. The 28 March 1768 edition of the "New York Gazette" (pg 3.), for example, mentions a farm in Jamaica, Long Island, New York, where nectarines were grown.
Source: http://en.wikipedia.org/wiki/Nectarines#Nectarines