Before you start, you will need a free API key from Google.
Before you start, you will need a specific API key from Google.
The key is free, and are required to complete this process.
Go to https://code.google.com/apis/console/, and log in with your Google Account.
The following will appear:

Click on the "Create Project" button.
In the list of services, find Google Maps API v3, and click on "off" to turn it on.
In the next screen, check "I Agree..." and the click the "Accept" button. You will now see that the button next to Google Maps API v3 has changed to "on".
Then click "API Access" in the menu to the left. It will ask you to "Create an OAuth 2.0 client id...".
In the next screen, provide a product name (e.g. "demo"), upload an image (if you want to) as a logo of your project, and click the "Next" button.
In the next screen, choose Application type ("Web application"), and type in your web address, and then click the "Create Client Id" button.
In the next screen, you have got an API key, and it will look something like this:

Note: Save your API key! (You will need it for all Google Maps applications you develop for the particular URL)
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