Educational technologies are often initially defined in terms of hardware: the computers or mobile devices students use and the networks — wired and wireless — that connect them. Technology is a tool or system used to solve problems. In education, that means things or tools used to support teaching and learning. Under this definition, educational technologies — as tools — can include software (such as word processors), systems (such as learning management systems), services (such as YouTube), and environments (such as virtual worlds), as well as the hardware and networks on which these all depend. It can also include traditional “technologies” such as blackboards and textbooks, though the focus here is on their online or digital counterparts. The other component of the definition is equally important: technologies solve problems. A tool becomes a technology when it is applied with some intention to meet some human need; the definition of educational technology will include its teaching or learning purpose. In many cases, this will mean delivering learning content as various forms of media (e.g., text, video, games), but it can also include social or collaborative activities (such as discussion boards or videoconferencing) or the creation of artefacts by learners (assessment activities or e-portfolios). The purposes educators identify and the problems their technologies are meant to solve reflect their values and priorities as educators; technological choices should go beyond whatever is trendy or new. A few categories of educational technologies that support teaching and learning are illustrated below.