purity rings

Purity ring,have been wear by Jonas Brother ,Miley Cyrus,Demi Lovato a,Selena Gomez and many more.Do you know what is a purity ? this some explanation,
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Purity rings (also known as chastity rings, promise rings, or abstinence rings) originated in the United States in the 1990s among Christian-affiliated sexual abstinence groups. The rings are sold to adolescents, or to parents so that the rings may be given to their adolescent children as gifts.
Wearing a purity ring is typically accompanied by a religious vow to practice abstinence until marriage. The ring is worn with the implication that the wearer will remain abstinent until it is replaced with a wedding ring.

Criticism
David Bario, a reporter in the Chicago Tribune, Rutland Herald, and several other news websites wrote:[1]
"Under the Bush administration, organizations that promote abstinence and encourage teens to sign virginity pledges or wear purity rings have received federal grants. The Silver Ring Thing, a subsidiary of a Pennsylvania Evangelical Church, has received more than $1 million from the government to promote abstinence and to sell its rings in the United States and abroad."
The ACLU of Massachusetts brought charges against this decision, because the Silver Ring program did not ensure its secularity and hence was ineligible for federal funding due to the Establishment Clause of the First Amendment. The settlement between the ACLU and the U.S. Department of Health and Human Services (HHS) says that any further similar applications of Silver Ring Thing must be reported to ACLU and closely scrutinized for separation of church and state.[2]