Deixis is a word of Greek origin meaning 'pointing'. Thus, words which are deictic 'point' to different times, spaces and people. The meaning of these words is dependent upon the context in which they are used.
For example: if a teacher stands at the front of a room, at 9.13am on Wednesday 28 June and says to a student 'I want you to come here now', then the following deictic words mean: