[jamessb]

Many (most?) conferences have both posters and talks. Posters have a few advantages:

- they parallelise well: you can fit a lot of posters in a room, and have a person standing beside each one talking concurrently

- it's easy to quickly glance at each poster in a room and move on if they're not of interest to you; it is harder to leave a talk that turns out to be uninteresting, and you can't be physically present for more than one talk at once

- they allow the presentation of a contribution that is currently too small to form the basis of a complete talk, which lets people get early feedback and advice (and gives students at an early stage in their PhD a chance to present something)

In some venues people have interactive demos beside their poster, running on a laptop/iPad/monitor.

At some conferences there is a session where a short (e.g. 30s) video for each poster is played as an advertisement.

Posters can give rise to deeper conversations, but they can also be more or less completely ignored (whereas a talk would have at least a few people in the audience).