In this post, I am going to explain about the standard objects which will be created by default the moment you enable Live Agent in your organization. Let’s start –

Live Chat Visitors:
This object contains information about the visitors who has initiated the chat session. One important field here is the Session Key. A session key in a unique record which is stored on Live Chat Visitor’s record and end user’s machine as a cookie. But why? The reason is if the end user is initiating multiple chat sessions, then Salesforce will link all Live Chat Transcripts records (This is another object, which I will explain in a few minutes) to this unique Live Chat Visitor record. Here is a sample Live Chat Visitor record.


Live Chat Transcripts:
This is the record which tells you the conversation that happened between your Service Representatives and End Users. It stores the chat transcripts. Salesforce will automatically create the record for you as soon as the chat session is ended and your service representatives close the chat transcript. Here is sample Live Chat Transcript record.

Live Chat Transcript Events:
This object tracks all the events that occur between Service Representatives and Customer during the chat. Few important events are like Chat Request, Accept Request, Route Information, Transfer information. You can see the detail of events – 
https://help.salesforce.com/articleView?id=live_agent_transcript_events.htm&language=en&type=0
Here is sample Live Chat Transcript Event record.


Live Agent Sessions:
This object holds the information about the agent sessions, time spent online, time spent chat, idle time etc. Here is sample Live Agent Session record.


Quick Text:
Quick Text is a very handy option when chatting with customers. If your Sales Representatives are using few sentences quite a number of times, then instead of asking them to write the same again and again you can create Quick Text. It is basically the shortcut for commonly used phrases/questions.
Below is a sample Quick Text for greeting customers with Good Morning.


Now from the chat window, your Sales Representatives can just enter ;; and all available Quick Texts will be available to them. They can select the one. This was it will help them to respond back to the customer much quickly.