**4. Ubiquitous computing and ambient intelligence**

The most recent HCI study is unquestionably ubiquitous computing (Ubicomp). The phrase frequently used by ambient intelligence and pervasive computation interchangeably, refers to the ultimate human-computer interface techniques, which are the elimination of a desktop and the integrating of the computer in the environment in order to make it unseen to humans when covering them everywhere. Mark Weiser first proposed the concept of ubiquitous computing during his time as chief technologist at Xerox PARC's Computer Science Lab in 1998. His vision was to incorporate machines into the world and ordinary objects anywhere so that individuals could connect with several computers at the same time because they are hidden to them and communicate with each other wirelessly [29].

The Third Era of computation has also been called Ubicomp. The first era was the mainframe era, with one machine and several people. Then it was the Second Era, one user, one computer, named the PC era, and now Ubicomp introduces more machines, one person era [29]. The major developments in computation are seen in **Figure 3**.

**Figure 3.** *Major trends in computing [29].*
