A String is a Word or a text.
The [] always indicates that we have an Array of something, a list.
In your case a list of Strings (String[]). For a high score that means, first line in the list is lines[0], 2nd is lines[1] etc., could be Paul 10 in 1st line, Frank 8 in 2nd line. To read all lines, often for-loops are used to loop over the lines in the list.
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