Article 370 of the Indian Constitution is a 'temporary provision' which grants special autonomous status to Jammu & Kashmir. Under Part XXI of the Constitution of India, which deals with "Temporary, Transitional and Special provisions", the state of Jammu & Kashmir has been accorded special status under Art370. All the provisions of the Constitution which are applicable to other states are not applicable to J&K. For example, till 1965, J&K had a Sadr-e-Riyasat for governor and prime minister in place of chief minister
After J&K's accession, National Conference leader Sheikh Abdullah took over reins from Dogra ruler Maharaja Hari Singh and in 1949, he negotiated the state's political relationship with New Delhi, which led to the inclusion of Article 370 in the Constitution.
History.....
Sheikh Abdullah had argued that Article 370 should not be placed under temporary provisions of the Constitution. He wanted "iron clad autonomy" for the state, which the Centre didn't comply with.
Provisions...
According to this article, except for defence, foreign affairs, finance and communications, Parliament needs the state government's concurrence for applying all other laws. Thus the state's residents live under a separate set of laws, including those related to citizenship, ownership of property, and fundamental rights, as compared to other Indians. As a result of this provision, Indian citizens from other states cannot purchase land or property in Jammu & Kashmir.