"In classical film, time flows chronologically and is represented through progressions of shots that, in connecting time to sensory-motor references, represent it in a continuous fashion. Time ellipses and flashbacks add a degree of sophistication to to this representation of time, but they do not alter the essentially linear nature of movement-image progressions, designed to create spatio-temporal coherence."
It then goes on to cite Alain Resnais' Last Year in Marienbad as a good example of a non-linear structure "characterized by the intensive use of flashbacks and time shifts that are far from obvious and that create the time ambiguity..."
Howells, R & Negreiros, J (2012) Visual Culture. Cambridge: Polity Press
There are, of course, dozens of great films which have a non-linear narrative. Notable ones would be 21 Grams; Oldboy 2003; Pulp Fiction; Slumdog Millionaire; Kill Bill Vols 1&2; Mulholland Drive, Memento and Before the Devil Knows You'r Dead. It is increasingly common as film professionals need to create even more impressive new work to attract audiences. Often these come in the form of 'puzzle' movies such as Donnie Darko.
One of the best films depicting the contraction of time is Synecdoche, New York (2008) - written and directed by Charlie Kaufman. This is a mind-blowing piece of work which needs to be watched several times and my attempts to explain it could not do it justice. In one short scene, depicting a single incident which should cover a couple of days at most, time actually progresses by six months, indicated by a radio, a newspaper, Christmas decorations and a calendar.
Another good example is the scene in Notting Hill (1999, dir Roger Michell) where the protagonist walks through the market. It is done in one take, the camera tracking Hugh Grant but he walks into Autumn rain, Winter snow, Spring and the hot overhead sun of Summer. Other visual clues include a pregnant shopper whom we see at the end with toddler and a character newly in love later seen breaking up with her boyfriend; even the produce on the market stalls changes to match the season.
Other techniques could include light moving across a room to denote the hours of the day. Pages being torn off calendar. Hairstyles and cars are often used. In Shawshank Redemption we sense the passage of time by the changing posters on the wall of Andy's cell.
The expansion of time is more rare is this is unlikely to appeal so much to an audience. In basic terms this can simply be done through slow motion. The Matrix uses this technique to good effect.
Another technique is to shoot some action from a number of different viewpoints and repeat the playing of the incident. This can be a good narrative device if there is a complicated event occurring. A good example would be in Jackie Brown (1997, dir Quentin Tarantino) - the shopping bag exchange scene which we see three times.
Occasionally a film uses real time as a central part of the narrative - High Noon (1952, dir Fred Zinnemann) being one of the most famous examples of this. We see a clock repeatedly to build up tremendous tension.
Graphics can be used - text on the screen; time-laps; the aging process; symbolism; montage; transitions such as jump cuts or fades and dissolves. Colour techniques such as bleaching or filters. Split screens can also sometimes work in the case of multiple threads.