| In what year did this first occur... | Year |
| 1. | When did they first allow overhand pitching? | |
| 2. | When did they start calling strikes? | |
| 3. | When did they start calling balls? | |
| 4. | Was it always 3 strikes for an out? | |
| 5. | When did it change to 4 balls for a walk? | |
| 6. | When did they start calling all pitches? | |
| 7. | When did they stop allowing bound outs? | |
| 8. | When did home plate become 5-sided? a square? | |
| 9. | When did the base ball become the size it is today? | |
| 10. | When did the pitching distance become 60 feet 6 inches? | |
| 11. | When did they start using a batter's box? | |
| 12. | When did all foul balls start being counted as strikes? | |
| 13. | When did they start allowing the runner to overrun first base? | |
| 14. | When did the infield fly rule come into existence? | |
| 15. | When did a ball have to pass 1st or 3rd base fair to be a fair ball? | |
| 16. | When did a batter hit by a pitch get awarded 1st base? | |
| 17. | When were runners allowed to return to their bases on a foul ball without risk of being put out? | |
| 18. | When did the catchers start wearing gloves? | |
| 19. | When did the fielders start wearing gloves? | |
| 20. | When did the length of a bat become limited to 42 inches? | |
| 21. | When did the 9-inning game first become instituted? | |
| 22. | When was the choice of innings (up first or last) given to the captain of the home team? | |
| 23. | When was the batting order changed so that the lead-off batter after the first inning was the batter who followed the last batter who had a full turn at bat? | |
