re: Growing Garlic: tips & experiences

This past spring I tried growing garlic for the first time and it was a failure.
I had sprouted some garlic indoors and then planted it in the garden.
I got nothing.

Fast forward to today (October 31) and I see a row of garlic has spring up. Well, that is exciting. Or is it?

I realized that I know nothing about what to expect for garlic-growing.
I had planted more garlic this fall and it, too, has sprouted and is growing beautifully.

Fall growth: Is this normal? 
Should it have stayed dormant until the spring? 

Thanks in advance for your help, fellow homesteaders.
- Debbie