The csv file is encoded as UTF-8 and deploys comma (,) as field separator and quotation marks (") as field surrounding.
It was originally published on OSF. Cite as:
Katja Mellmann: Thompson's Motif-Index as CSV File. Open Science Framework (OSF), 2020. DOI: 10.17605/OSF.IO/XEB67.
The primary publication the csv file refers to is:
Stith Thompson: Motif-Index of Folk-Literature. A Classification of Narrative Elements in Folktales, Ballads, Myths, Fables, Mediaeval Romances, Exempla, Fabliaux, Jest-Books, and Local Legends. Revised and enlarged ed. 6 vls. Bloomington, IN: Indiana University Press 1955-1958.
For further information see the Wiki page on Source Information.
The main purpose of the csv file is to generate a reference table within a relational database (of folklore or different kinds of datasets).
It is not especially useful as a means to search for particular motifs. For that purpose, one might rather use the MOMFER - Meerten online motif finder; cf.
Folgert Karsdorp, Marten van der Meulen, Theo Meder, Antal van den Bosch: MOMFER. A Search Engine of Thompson's Motif-Index of Folk Literature. In: Folklore 126 (2015), no. 1, 37–52. https://doi.org/10.1080/0015587X.2015.1006954
For other & advanced uses of the TMI, you might profit from
Thierry Declerck, Antónia Kostová, Lisa Schäfer: Linked Data Access to Folktales classified by Thompson's Motifs and Aarne-Thompson-Uther's Types. In: Rhian Lewis et al. (Eds.): Digital Humanities 2017 (DH2017), Montréal, August 8-11, 2017, Conference Abstracts. Montréal: ADHO, https://dh2017.adho.org/abstracts/465/465.pdf