In some courses (but rather rarely), yours truly uses an automated curve (based on the Gaussian distribution: see the figure below: local link / general link: gaussian.html) to assign letter grades during the semester if there are enough students to make the automated curve meaningful and if the course is being taught by in-person instruction.

There should be 30 or so students to make the automated curve meaningful.

Curving is only used for current total grade: individual items (tests, etc.) are NOT curved.