When the time comes to leave work, you can do whatever you want. You can raise hell, say you hate everyone and yell out, 'I quit!!!' But in other cases when you want to leave professionally, you can use this lesson to help.
There's a common phrase when you are leaving a company. 'Don't burn the bridge.'
This is basically saying you should leave on a good term. If you leave on a good note, then you have the option of coming back to the company or your position if something goes wrong with your next job. So basically, you are leaving the bridge back to your position.
If you are leaving because you have an offer from a different company, here are some professional statements you can make to your manager.
Remember that in the States, changing job is very common. So it is no big deal when you leave a company. Businesses understand the need for change and realize that some people want different challenges in their life. So don't be nervous when you have to leave.
Giving a two week notice is standard. This gives your current employer the chance to hire someone to replace you. It also gives some time for you to finish the remaining work you have to do. Not giving a two week notice is one way to burn a bridge. The new company you are going into should realize this and will not expect you to start your job immediately if you have to give a two week notice. If you don't have a job, then this doesn't apply to you.
I have seen some people leave the company to go on a year trip around the world. Others I have seen just wanted to spend more time with their kids. I know in some countries it is hard to get back into a company after you leave, but in the States, if you are a good employee, it is easy to get their job back. Many times after a long break, they returned to the same company.