https://www.cnet.com/news/google-doodle-celebrates-st-patricks-day-with-celtic-triskele/

The Triskelion – also known as the Triple Spiral – features three interlocking spirals positioned to appear in constant motion, moving outward from the center. The action of the Triskelion's three spirals is often thought to reflect cycles, progress and revolution.   

The ancient symbol is open to a wide variety of interpretations but is typically associated with a trinity of themes. For some, it represents life, death and rebirth;  past, present and future; and spirit, mind and body, just to name a few.