How to initiate and receive voice and video calls from within Gmail?

This blog post explains how to set up Gmail so it will be able to initiate and receive voice and video calls.

1. Download and install the Google Talk Plugin from here.
2. Restart your browser, preferably Google Chrome.
3. Log into gmail in your browser.
4. In the top right corner click on the cogwheel icon, and then select Mail settings.
5. In the Chat tab, set up the settings of Voice and video chat.
6. Click on Verify your settings and make sure it works properly.
7. Save the settings (Save Changes).
8. Select a friend in the chat list, open a chat window. In the chat window there will be a phone or camera icon, with which you can start the voice or video chat.