The overview of the techniques we use is divided in two sections: first, the etching, where the work is inscribed in the copper plate, and then printing, where the work is transferred by the ink to the paper.
The word etching can either describe the resulting image itself, or, alternately, the technique used to produce this work. In the last centuries, the works of drawing, etching and printing were done by different persons, although there were artists, and not the least (Dürer, Piranesi, Rembrandt, to name but three), that were practicing all these disciplines, from creation to printing. In french dictionaries, they were named peintre-graveurs, to distinguish them from the reproduction printers.
Today, etching is not a means of reproduction anymore (except for stamps and bank notes, and what is called securities printing), but it is a medium that enables artists to create original works of great material and pictorial quality.
Intaglio is the ensemble of printmaking techniques where the image is formed by ink coming from recessed areas of the plate, by opposition to relief printing; both are different from lithography and serigraphy, where no relief nor recessed area is involved. Here is a classification of the different traditional techniques of what is loosely called etching:

There are many more ways today to make intaglios, many artists mix techniques in infinite variations, but we have chosen to practice this discipline using traditional tools.