A chatbot is a computer programme powered by rules and, sometimes, artificial intelligence, with which the user interacts via a chat interface. They determine the intent and extract data from the users’ sentences, and respond accordingly. Simpler ones are based on explicitly creating rules from top-down (pre-made answers to specific questions), while others use machine learning algorithms to learn the tasks from a large corpus (a collection of written texts) of transcribed interactions. The experience could range from functional to fun, and it could live in any major chat product. Instead of browsing a website, you would have a conversation with a bot, mirroring the type of experience you would get, for instance, when going into a retail store. As people are now spending more time in messaging apps than in social media, this is a huge turning point as the bots evolve into the tool to provide users with services. This paradigm shift is seen as an opportunity for creating new businesses. Having the user interact with elementary user interface with immediate and hassle-free access to products and services could be a big deal, as their attention spans could be more receptive comparing to a new website or a new app. 
As the technology evolved, a few companies started to think about experimenting and applying bots towards the benefit of individuals with a variety of conditions such as Alzheimer’s, depression, loneliness, and even insomnia.
Chatbots can provide active advice and awareness
There are almost 10 million new cases of Alzheimer's each year. In the early stages, the main symptom is memory lapses, and as it progresses, there is an onset of other symptoms, such as confusion, delusions or amnesia. This takes the autonomy away from the patient, pushing him/her to becoming more and more self-contained.
In order to improve the quality of life of Alzheimer’s patients, Italia Longeva, the Italian national research network on ageing and active longevity, in partnership with the Italian Ministry of Health, created a chatbot app that helps patients remembering things by chatting to them. It collects patient data from Facebook, and through artificial intelligence, it’s trained to answer a lot of different needs, in real time and at any location, such as remembering names, reaching places, assisting in performing daily tasks and many others. The objective is to improve the lifestyle of Alzheimer’s patients in their early stages, giving them back some independence in order to interact with the world around them, while still supporting their families .
Other companies, such as Endurance, are focused on creating a universal robot-companion (SelfieBot) for senior people, as they want to provide them, as well as patients with Alzheimer’s, the opportunity to communicate, share experiences and memories. It is assumed that the robot will be able to conduct conversations on more than 20 topics, such as: weather, nature, news, history, cinema, music, etc., and faces the task of not only having to ask and answer questions but also to memorize the context of the conversation and recognize the tone of the user, which is crucial for conducting a cohesive dialogue .
Chatbot features can help solve a lot of challenges that the older generation faces by simply providing companionship. Loneliness and depression are two of the biggest problems of our time. Sometimes people talk to themselves or to their pet, so having a conversation with a bot would at least be closer to a human response, as an intelligent system on the other side is able to generate a relatively natural conversation. It goes further than simple interaction though – for example, a consumer artificial intelligence app called Replika  learns more about the user the more it engages with him/her over text. It will ask you about your day, and talk to you about your goals and interests. However, the company also states that it takes "thousands of hours" for the bot to become a faithful digital representation of its user. This might also help some people to develop and practice social skills, in case they lack them.
"It allows you to have a sort of a safe space to reflect and try to understand yourself a little better," says Eugenia Kuyda, CEO and founder. "It's there for you to talk about anything, and help you feel witnessed and seen." 
Other applications and different approaches
A company called Intuition Robotics developed ElliQ , a pro-active artificial intelligence driven social robot designed to encourage an active and engaged lifestyle by using machine learning to understand the preferences of the users to suggest activities, and making it simpler to connect with loved ones. Besides talking, ElliQ also uses non-verbal forms of communication, which try to make language or communication more understandable for elderly people while ensuring they do not feel alone .
Chatbots are also used to help people of all ages. For example, Casper entered the world of artificial intelligence by rolling out a chatbot targeted towards people who are having trouble sleeping. Insomnobot3000  is designed to respond to your texts between 11 p.m. and 5 a.m. It has a wide range of responses honing in on the oft-repeated subjects, and a universally friendly personality, but as it doesn’t use machine learning, it won't grow smarter on its own. Nevertheless, it will understand common phrases and pop culture references, and will also occasionally initiate late-night conversations to make the interaction appear more real, so if you’re feeling sleepy, you might just want to turn off those notifications .
Machines contributing to society
These chatbots and physical robots can prove valuable to assisting senior citizens, both as companions and also as tools to maintain their physical and mental health. As the technology evolves, they should be able not only to fill that void for lonely people, but also provide patients with Alzheimer’s with reminders about names, places or tasks, as well as try to improve their memory with games. We cannot say that robots can yet replace a real conversation with a human, but talking to a bot can help almost as much as doing so with one, filling a void for an age group in need of social interaction, assistance and support.