In the novel "The Westing Game" by Ellen Raskin, Sydelle Pulaski's shorthand notes are unique because they are written in a special code that only she understands. Sydelle, who is a secretary, has a habit of writing down conversations and observations in shorthand. However, she uses her own personalized shorthand system, which includes symbols and abbreviations that are not conventional shorthand.
Sydelle's shorthand notes become significant in the context of the Westing Game mystery because they contain information and clues related to the game's various puzzles and secrets. The other characters in the story are puzzled by her notes because they cannot decipher her code. Sydelle's shorthand notes become a key element in unraveling the mysteries of the Westing Game and serve as a source of intrigue and suspense throughout the novel.