Chuck Geschke, co-founder of Adobe Systems and a key developer of the PDF format, has passed away at the age of 81. His contributions to digital document management revolutionized how information is shared and stored, making PDFs a standard format across various industries. Many users express gratitude for his invention, highlighting its utility in note-taking, web captures, and information organization. Geschke's legacy is marked by innovation and a lasting impact on technology. His work continues to facilitate communication and documentation in the digital age.