To inspire the next generation of explorers, NASA reaches out to students in schools, community organizations, and public events. A star robotic ambassador is “Rov-E,” a close replica of real NASA Mars rovers. Through Amazon Lex, NASA staff can now easily navigate Rov-E via voice commands -- an effective conversational interface when speaking with large crowds. Multi-turn dialog management capability enables Rov-E "to talk,” answering students’ questions about Mars in an engaging way. Integration with AWS services allows Rov-E to connect and scale with various data sources to retrieve NASA’s Mars exploration information. 
This is a lot less complicated than it appears. Given a set of sentences, each belonging to a class, and a new input sentence, we can count the occurrence of each word in each class, account for its commonality and assign each class a score. Factoring for commonality is important: matching the word “it” is considerably less meaningful than a match for the word “cheese”. The class with the highest score is the one most likely to belong to the input sentence. This is a slight oversimplification as words need to be reduced to their stems, but you get the basic idea.
I argued that it is super hard to scale a one-trick TODA into a general assistant that helps the user getting things done across multiple tasks. An intelligence assistant is arguably expected to hold an informal chit-chat with the user. It is this area where we are staring into perhaps the biggest challenge of AI. Observe how Samantha introduces herself to Joaquin Phoenix’s Ted in the clip below:
With the help of equation, word matches are found for given some sample sentences for each class. Classification score identifies the class with the highest term matches but it also has some limitations. The score signifies which intent is most likely to the sentence but does not guarantee it is the perfect match. Highest score only provides the relativity base.
Founded by Pavel Durov, creator of Russia’s equivalent to Facebook, Telegram launched in 2013 as a lightweight messaging app to combine the speed of WhatsApp with the ephemerality of Snapchat along with claimed enhanced privacy and security through its use of the MTProto protocol (Telegram has offered a $200k prize to any developer who can crack MTProto’s security). Telegram has 100M MAUs, putting it in the second tier of messaging apps in terms of popularity.
“The chat space is sort of the last unpolluted space [on your phone],” said Sam Mandel, who works at the startup studio Betaworks and is also building a weather bot for Slack called Poncho. “It’s like the National Park of people’s online experience. Right now, the way people use chat services, it’s really a good private space that you control.” (That, of course, could quickly go sour if early implementations are too spammy or useless.)

[In] artificial intelligence ... machines are made to behave in wondrous ways, often sufficient to dazzle even the most experienced observer. But once a particular program is unmasked, once its inner workings are explained ... its magic crumbles away; it stands revealed as a mere collection of procedures ... The observer says to himself "I could have written that". With that thought he moves the program in question from the shelf marked "intelligent", to that reserved for curios ... The object of this paper is to cause just such a re-evaluation of the program about to be "explained". Few programs ever needed it more.[8]