What is Chat-bot?

Short for chat robot, a computer program that simulates human conversation, or chat, through artificial intelligence. Typically, a chat bot will communicate with a real person, but applications are being developed in which two chat bots can communicate with each other. Chat bots are used in applications such as e-commerce 
customer service, call centers and Internet gaming. Chat bots used for these purposes are typically limited to conversations regarding a specialized purpose and not for the entire range of human communication.
One well known example of a chat bot is ALICE.
A chat bot is also called a chatter bot.

What are the biggest advantages and disadvantages of using chat-bots?


The biggest advantages of chat-bots include being able to reach a broad audience on messenger apps, as well as the ability to automate personalized messages. They also can improve efficiency by taking over tasks for which humans are not essential. One disadvantage is that not all bots are created equal. For example, when Facebook opened up messenger to bots, many people were disappointed in the lack of sophisticated entry level bots were able to provide. However, this will improve over time, with better bot selection. 
There are thousands of chat-bots in India as of now but I am going to list only which are famous by itself or Launched by Big Brands Like HDFC, Yatra etc.
1. Engazify
Engazify Bot is a faster and better way to appreciate your teammates, capture all your team wins, and save it for everyone to see.
2. GoHeroAI
It assists you in booking flight, hotel, taxis etc. It integrates with messaging apps to use sophisticated algorithms and understand traveller’s preference.
3. HDFC
Eva is India's first AI-based banking chatbot and can answer millions of customer queries across multiple channels instantly, HDFC Bank said in a statement.
4. Ruhh
A chatbots developed by Microsoft India team. Specially for Indian market. You can talk in English as well Hindi.
5. Lawbot
This Chennai-based chatbot or rather Lawbot analyses and reviews legal documents, like license agreements, which can help you save time, money and simplify the process
6. Haptik
Haptik can perform a wide array of activities ranging from finding the best shopping deals, checking train status, book movie tickets, get food delivered, and book flight/train tickets among others.
7. Gupshup
it enables developers to quickly and easily build, test, deploy and manage chatbots across all messaging channels.
8. IxiBaba
A chatbot that can answer all your travel queries, brought to you by ixigo is the perfect example of how companies are improving on interacting with customers and enhancing customer experience.
9. MagicX
One of the first bots on the Facebook messenger, MagicX lets you carry day-to-day tasks like bill payments, recharge, food ordering, flight booking and other services via chat.
10. Niki.ai
Whether a prepaid, post-paid or DTH recharge, paying electricity bills, booking a cab, getting a laundry or ordering a burger from burger king, this chatbot assists you in all of it.
11. RechargeBot
Payjo is India’s first messenger bot that lets you recharge your phone, sets reminder for recharge and shows suitable plans for your number.
12. Yana
YANA help users to book cabs, order groceries, etc. The chatbot’s intelligence has been developed by it’s more than 50,000 messages that it has received over time.
13. FitCircle
FitCircle is a health and fitness chatbot which offers users personalized weight loss workouts, personalized yoga guidance and similar features. It also offers nutrition guidance.
14. Prepathon
Prepathon messages students the topic of the day, it answers questions and also sends across motivational messages. Aimed at helping students perform better at their exams, this chatbot is making their life easier
15. Yatra
Yatra has launched what it claims is the first Facebook Messenger chatbot in the Indian online travel sector. The intelligent chatbot helps customers search and book flights directly from their Facebook Messenger.
Go for a click and enjoy it.