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README.md

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 ##### Description
 
-`read_csv` operator transforms a csv file in to Tercen datasets. Tercen itself has a 'Delimited text' file import but you can't use that one in a workflow step. 
+`read_csv` operator transforms csv files into Tercen datasets. It can upload an individual CSV file or multiple CSV files in a zipped folder.
+
+CSV files (.csv) are text files which use a comma as the delimiter.
+
+(Tercen also has a 'Delimited text' file importer with settings for both comma and other delimiter types. It has more advanced features for data maipulation but cannot be embedded as a file importer in a workflow.) 
 
 ##### Usage