Collage is a technique involving cutting out shapes and gluing them to make a new arrangement. As such it allows artists to achieve images which cannot be made any other way.
The Cubists - Picasso and Braque used the technique to include typography into their art.
The Dadaists - invented photo-montage; to shock the viewer with distorted and disfigured portraits.
And of course, the most recognizable collages are probably by Matisse, who took to "cut-outs" when illness made traditional painting impossible.
So it is, collage has been recognized as an acceptable form of creation.
Some of the artists on the gallery choose to cut and paste virtually, printing the image after assembly.
Cone Banksia - Light
Sally Maltby
Others, combine a variety of found objects in their work.
Yet more, follow the Dada route - producing images meant to shock.
Apocalypse Wow!
Freelance Wizard
For another artist, the attraction is the cleanliness of lines when cut.
ABSTRACT WITHIN GRID
Stephen Conroy
And, then sometimes combined with paint.
Little Garden number 18
Stephen Powlesland
Even more, use collage to build up images in a similar way, to that used by most artists, imitating brushstrokes.
And even more, use collage like spots of paint almost like the Pointillists.
Cheryl - Singing the Blues
Peter Mason
By now, I think you've got the idea — collage has no boundaries.