The vedas are 4- Rigveda, Yajurveda, Samaveda and Adharvaveda. All of them are collections and are known as Brahmanas. They were later supplemented by Aranyakas and then by Upanishads. The vedas, with brahmanas, aranyakas and upanishads are together called Vedasahitya. The Aranyakas and Upanishads are connected strongly. Upanishads are also called Vedantas. All the vedantas were created in the final eras of the vedic period. After studying mantras and brahmanas, students used to learn upanishads. ‘Upanishad’also translate to the ‘nearest located’. They are closest to brahmaswarupa. The meaning of the vedas can be grasped from the upanishads. Though they seem to be the interpretation of mantras, they also contain the details of the origin of life, and discussions on the meanings of world, soul, god etc. Though there are many upanishads, 108 of them are the most important. They are

1. Brahmopanishad 2. Brahmavidya Upanishad 3. Kshurikopanishad 4. Yogatatva Upanishad 5. Subala Upanishad 6. Mandalabrahmana Upanishad 7. Kaushitakibrahmana Upanishad 8. Jabaladarshana Upanishad 9. Hamsopanishad 10. Swasamvedyopanishad 11. Jabalyupanishad 12. Maitreyi Upanishad 13. Shandilya Upanishad 14. Parabrahmopanishad 15. Karudropanishad 16. Kundikopanishad 17. Arunikopanishad 18. Sanyasa Upanishad 19. Naradaparivrajakopanishad 20. Paingala Upanishad 21. Mahavakyopanishad 22. Atmabodhopanishad 23. Kaivalyopanishad 24. Brahmabindupanishad 25. Aatmopanishad 26. Pancha-brahmopanishad 27. Sharirikopanishad 28. Shaatyayaniyopanishad 29. Yajnavalkyopanishad 30. Jabalopanishad 31. Paramahamsa Upanishad 32. Nirvana Upanishad 33. Paramahamsaparivrajaka Upanishad 34. Bhikshukopanishad 35. Avadhuta Upanishad 36. Ishavasyopanishad 37. Kenopansihad 38. Katthopanishad 39. Prashnopanishad 40. Mundakopanishad 41. Mandukyoapnishad 42. Aitareyopanishad 43. Taithariyopanishad 44. Chhandogyopanishad 45. Shwetashwataropanishad 46. Garbhopanishad 47. Mudgalopanishad 48. Akshyupanishad 49. Adhyatmopanishad 50. Maitrayanyopanishad 51. Shivasankalponishad 52. Ashramopanishad 53. Dwayopanishad 54. Vajrasuchikopanishad 55. Adharvashiropanishad 56. Skandopanishad 57. Sarvasaropanishad 58. Shukarahasyopanishad 59. Mantrikopanishad 60. Pranavopanishad 61. Niralambakopanishad 62. Gayatri-Upanishad 63. Amritanadopanishad 64. Ekaksharopanishad 65. Nadabindupanishad 66. Turiyatitopanishad 67. Yogarajopanishad 68. Aatmapujopanishad 69. Yogachundyopanishad 70. Mahopanishad 71. Trishikhabrahmanopanishad 72. Advayatarakopanishad 73. Pashupatabrahmopanishad 74. Pranagnihotropanishad 75. Yogakundulyupanishad 76. Dhyanabindupanishad 77. Akshamalikopanishad 78. Rudrakshajavalopanishad 79. Ramapurvatapinyupanishad 80. Gopalapurvatapinyupanishad 81. Krishnopanishad 82. Ganapatinyupanishad 83. Nrisimhapurvatapinyupanishad 84. Nrismhashtachakropanishad 85. Dakshinamurtyupanishad 86. Sharabhopanishad 87. Rudropanishad 88. Kalagnirudropanishad 89. Nilarudropanishad 90. Rudrahridayopanishad 91. Garudopanishad 92. Langulopanishad 93. Gayatrirahasyopanishad 94. Savitryupanishad 95. Saraswatirahasyopanishad 96. Devyupanishad 97. Vahvrichopanishad 98. Saubhagyalakshmyupanishad 99. Tripuropanishad 100. Sitopanishad 101. Radhopanishad 102. Tulasyopanishad 103. Narayanopanishad 104. Suryopanishad 105. Bhavanopanishad 106. Chaturvedopanishad 107. Chakshushopanishad 108. Kulisamtaranopanishad