informats instruct SAS on how to read data from any input location (such as a file, an excel spreadsheet, a named pipe, or even another SAS variable, etc.) into a variable.
SAS has just two data types - character and numeric, and each informat is specific to storing the value into either a character or numeric variable. If the destination variable is a character, then the informat will begin with a
$ symbol, anything else will be a numeric informat.