Update README.md (#40)

Added details about ADVANCED and BASIC AI models.

Author: trulyfurqan

README.md

@@ -160,6 +160,12 @@ settings:<br/>
 By default AI Model Type is set to ```ADVANCED``` and it can be overridden by running ```bito -m <BASIC/ADVANCED>```
 Model type is used for AI query in the current session. Model type can be set to BASIC/ADVANCED, which is case insensitive.
 
+"ADVANCED" refers to AI models like GPT-4 and Claude 2, while "BASIC" refers to AI models like GPT-3.5 Turbo and Claude Instant.
+
+When using BASIC AI models, your prompts and the chat's memory are limited to 40,000 characters (about 18 single-spaced pages). However, with ADVANCED AI models, your prompts and the chat memory can go up to 240,000 characters (about 110 single-spaced pages). This means that ADVANCED models can process your entire code files, leading to more accurate answers.
+
+If you are seeking the best results for complex tasks, then choose ADVANCED AI models.
+
 ##### Access Key
 Access Key can be created at Bito Web UI and used in Bito CLI.