GMail has this wonderful chat feature that lets you exchange IM text messages without your GMail contacts right inside the GMail webpage without even having to download the GTalk client.
But on the flip side, Google Talk [in the default settings] may do certain things that you not really enjoy. One, your Gmail contacts are pre-loaded into Google Talk.
Second, if you frequently communicate with someone using GMail, Google talk assumes that person to be your friend and automatically adds him to your contacts list. That means he will appear on your Google Talk friends list and will be able to see you exact online status with your picture and the status message.
Why this is bad ? Because if you exchange frequent emails with someone, it doesn't imply that he's your friend. For example, if someone copies your site content and you are trying to get the material removed from his site, he doesn't deserve to be on your GTalk friend's list even if you wrote a 100 emails to him.
Another case is blog commenters or even readers who write you tips. Say someone sends you a link to some story and you reply him saying "Thank you" - does that mean that he's now close enough to be on your friend's list or see your online status ? The answer would be no in most of the cases.
Fortunately, Google has provided a very easy way to override this default setting though most GTalk users rarely take the pain of exploring it. So take a few minutes off from your busy schedules and follow these steps below - this will save you tons of time [and those embarrassing moments] when you suddenly find a strange looking name in your Google Talk friend's list.
1. Open GMail and click the Settings link on the top right corner.
2. Open the Chat tab and change the "Auto-add suggested contacts" setting [see screenshot]
3. Select Only allow people that I've explicitly approved to chat with me and see when I'm online. Click save.
Quick Tip: Google lets you record your GMail chat sessions automatically as searchable emails in the Chat folder of your gmail inbox. Now suppose you are participating in a conversation with your friend but like to share a few links or say things that you would hate getting recorded.
To do this, click the down arrow of the chat client and choose Options -> Go Off the record. When you go off the record while chatting, nothing that's said from that point forward gets saved in either person's Gmail account.