Nuke is a “node-based” compositing application, originally developed by the visual effects company, Digital Domain, in Venice, CA. Originally developed as an in-house tool, Nuke was acquired by The Foundry in the UK a few years ago, and they have continued its development.
As with other node-based compositors such as Fusion from Eyeon, there is no concept of layers as there is with After Effects, Photoshop, Premier, and Final Cut Pro. Instead, you build various “node trees” to drive the compositing process. It is a very powerful way to work, and can allow for extremely complex affects to be created, and once created, easily controlled or changed. However, as always, that power comes at a price, and the ease of layers is completely discarded. As a result, composites that don’t require the level of complexity offered by nodes (more of them than not), simpler work becomes tedious and more time consuming. Node-based compositors are often found in feature film pipelines, though as prices have dropped, and computers have improved, television work is now frequently achieved with node-based compositors and After Effects, as well as other products.