What is the best way to deal with a 2.5 year old throwing tantrums, especially in public? Will this be a phase that will pass?

Welcome to the terrible two's stage. I'm experiencing this myself now too. What I do is, before we head out, I'll tell my lo in a stern manner to behave in public else she will be ''confined'' at home. But I believe kids forgets their promises after awhile, so I bring along her favourite toy, snack etc to "Pacify" her when we are in public. Worse comes to worse, I'll bring her to one area in public and allow her to vent all her unhappiness she has then I'll continue with whatever I need to do.