What is Lemon law?

Many people ask me what is Lemon law and i must again and again answer, but it is very easy use google. From now I send people here.
For strict and correct answer on this question is best quote wikipedia:

Lemon laws are United States state laws that remedies to consumers for cars that repeatedly fail to meet certain standards of quality and performance. These niche market cars are called lemons. The federal lemon law (the Magnuson-Moss Warranty Act) protects citizens of all states. State lemon laws vary by state and may not necessarily cover used or leased cars. The rights afforded to consumers by lemon laws may exceed the warranties expressed in purchase contracts. Lemon law is the common nickname for these laws, but each state has different names for the laws and acts.

And what is lemon:

A lemon is a defective car that, when purchased new or used, is found by the purchaser to have numerous or severe defects not readily apparent before the purchase. Any vehicle with these issues can be termed a 'lemon,' and, by extension, any product which has major flaws that render it unfit for its purpose can be described as a 'lemon.'

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