section_path: Structure/Quarks
section_name: Quarks
paragraph_text: Quarks
  
  Quarks are massive particles of spin- 1 ⁄ 2, implying that they are fermions. They carry an electric charge of − 1 ⁄ 3 e (down-type quarks) or + 2 ⁄ 3 e (up-type quarks). For comparison, an electron has a charge of −1 e. They also carry colour charge, which is the equivalent of the electric charge for the strong interaction. Quarks also undergo radioactive decay, meaning that they are subject to the weak interaction.