When I tab, my whole document is indenting. Why?

This uses Word's AutoFormat feature. To turn that feature off

  1. Open Word
  2. Open File -> Options
  3. Go to the Proofing menu
  4. Click AutoCorrect Options
  5. Click the AutoFormat as You Type tab
  6. Uncheck Set left- and first- indent with tabs and backspaces in the Automatically as You Type section
  7. Click OK