Designers carefully observe real-life situations for a set amount of time to understand how people behave within a given context. This method can help to uncover the reality of what people really do – as opposed to what they say they do. Shadowing an individual on a journey or activity can be used to identify opportunities for design and quickly understand a particular design context. Generally, there are three types of observation: natural (covert) – no interference from the investigator; controlled (overt) – the designer sets a task and observes it being carried out; and participatory – the designer actively joins in the activity being observed to gain a firsthand perspective.