Extracts n number of characters from the beginning of a string.
n is the length of the substring you want to extract. The length can be a constant, a numeric field, an expression that results in a number or a function that returns a number.
This function returns a character string.
Calculated field example
If the Company field contained the value Widgets Inc, the following calculated field expression would return Widgets: Left(Company,7)
Records with a Company field value of Wright Corp or Wright Brothers can be selected or found using the expression: Left(Company,6)="Wright"