This review discusses the fuzzball proposal for black holes in string theory. Samir D. Mathur presents an elementary overview of black holes in string theory, focusing on BPS holes, the microscopic computation of entropy, and the 'fuzzball' picture of the black hole interior. The review addresses the information paradox, which arises from the apparent loss of information when a black hole evaporates via Hawking radiation. The paradox is resolved in string theory by showing that the black hole interior is not a singularity but a complex structure of microstates, with the information encoded in the quantum states of the black hole. The review begins by introducing the Bekenstein entropy formula, which assigns entropy to black holes based on their horizon area. It then discusses the challenge of finding microstates for black holes, as traditional methods failed to find them. The fuzzball picture suggests that the black hole interior is not a singularity but a complex structure of microstates, with information distributed throughout the 'fuzzball'. The review then explores how black holes can be constructed in string theory. It discusses the role of BPS states, which are stable configurations that preserve some supersymmetry. The review also considers the 1-charge, 2-charge, and 3-charge solutions, showing how the Bekenstein entropy can be matched with the microscopic entropy computed from the number of microstates. The review highlights the importance of dualities in string theory, which allow the transformation of different types of black holes into each other. It discusses the entropy of the NS1-P bound state and shows that the microscopic entropy matches the Bekenstein entropy. The review also considers the three-charge system, where the entropy is calculated and shown to agree with the Bekenstein entropy. Finally, the review discusses the construction of microstates for black holes, emphasizing the importance of understanding the structure of the black hole interior. It notes that the black hole interior is not a singularity but a complex structure of microstates, with the information encoded in the quantum states of the black hole. The review concludes that the fuzzball picture provides a resolution to the information paradox by showing that the black hole interior is not a singularity but a complex structure of microstates.This review discusses the fuzzball proposal for black holes in string theory. Samir D. Mathur presents an elementary overview of black holes in string theory, focusing on BPS holes, the microscopic computation of entropy, and the 'fuzzball' picture of the black hole interior. The review addresses the information paradox, which arises from the apparent loss of information when a black hole evaporates via Hawking radiation. The paradox is resolved in string theory by showing that the black hole interior is not a singularity but a complex structure of microstates, with the information encoded in the quantum states of the black hole. The review begins by introducing the Bekenstein entropy formula, which assigns entropy to black holes based on their horizon area. It then discusses the challenge of finding microstates for black holes, as traditional methods failed to find them. The fuzzball picture suggests that the black hole interior is not a singularity but a complex structure of microstates, with information distributed throughout the 'fuzzball'. The review then explores how black holes can be constructed in string theory. It discusses the role of BPS states, which are stable configurations that preserve some supersymmetry. The review also considers the 1-charge, 2-charge, and 3-charge solutions, showing how the Bekenstein entropy can be matched with the microscopic entropy computed from the number of microstates. The review highlights the importance of dualities in string theory, which allow the transformation of different types of black holes into each other. It discusses the entropy of the NS1-P bound state and shows that the microscopic entropy matches the Bekenstein entropy. The review also considers the three-charge system, where the entropy is calculated and shown to agree with the Bekenstein entropy. Finally, the review discusses the construction of microstates for black holes, emphasizing the importance of understanding the structure of the black hole interior. It notes that the black hole interior is not a singularity but a complex structure of microstates, with the information encoded in the quantum states of the black hole. The review concludes that the fuzzball picture provides a resolution to the information paradox by showing that the black hole interior is not a singularity but a complex structure of microstates.