How do you left click on a Mac without a mouse?

Related questions

1. How can I use one mouse with two laptops?
2. How do I control Windows without a mouse?
3. Can I hook up two computers to one monitor?
4. What is half life decay?
5. Does Half Life 2 have multiplayer?
6. What is synergy tool?
7. How do I switch from one screen to another using the keyboard?
8. What is synergy app?
9. What does Synergy Software Do?
10. Can you play Half Life 2 coop?

Tags

1. #either
2. #option
3. #press
4. #button
5. #right
6. #space
7. #click
8. #mouse
9. #confuse
10. #control
11. #trackpad
12. #keyboard