What is creamy layer according to Supreme Court

Whether "Creamy Layer" is to be excluded from SEBCs? (Socially and Economically Backward Classes)
"Creamy Layer" is to be excluded from SEBCs. The identification of SEBCs will not be complete and without the exclusion of "creamy layer" such identification may not be valid under Article 15(1) of the Constitution. (Paragraph 152)
7. What should be the para-meters for determining the "creamy layer" group?
The parameters contained in the Office Memorandum issued by the Government of India, Ministry of Personnel, Public Grievances and Pensions (Department of Personnel and Training) on 08.09.1993 may be applied. And the definition of "Other Backward Classes" under Section 2(g) of the Act 5 of 2007 should be deemed to mean class or classes of citizens who are socially and educationally backward, and so determined by the Central Government; and if the determination is with reference to caste, then the backward class shall be after excluding the creamy layer. (Paragraphs 153 and 155)
8. Whether the "creamy layer" principle is applicable to Scheduled Tribes and Scheduled Castes?
"Creamy Layer" principle is not applicable to Scheduled Castes and Scheduled Tribes. (Paragraph 163)

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