A Sparkline is a small intense, simple, word-sized graphic with typographic resolution. Sparklines mean that graphics are no longer cartoonish special occasions with captions and boxes, but rather sparkline graphics can be everywhere a word or number can be: embedded in a sentence, table, headline, map, spreadsheet, graphic. Data graphics should have the resolution of typography. (Edward Tufte, Beautiful Evidence, 46-63.)
A Win-loss Sparkline only shows whether each value is positive or negative, whereas a Sparkline shows how high or low each value is.