What is etching?

Related artists: Franz ACKERMANN | Pierre ALECHINSKY | Karel APPEL | Enrico BAJ | Joseph BEUYS | Michael BORREMANS | Louise BOURGEOIS | Vija CELMINS | Sandro CHIA | Eduardo CHILLIDA | Francesco CLEMENTE | Guillaume CORNEILLE | Enzo CUCCHI | Thierry DE CORDIER | Wim DELVOYE | Martin DISLER | Lucio FONTANA | Sam FRANCIS | Helen FRANKENTHALER | Keith HARING | Damien HIRST | Allen JONES | Anish KAPOOR | Alex KATZ | William KENTRIDGE | Jonathan MEESE | Bruce NAUMAN | Constant NIEUWENHUYS | Mimmo PALADINO | A.R. PENCK | Robert RAUSCHENBERG | Richard SERRA | Rafael Jesus SOTO | Antoni TAPIES | Walasse TING | Bernar VENET | Carlos CRUZ-DIEZ | Rene MAGRITTE | Sonia DELAUNAY | Markus LUPERTZ | Conrad MARCA-RELLI | Donald BAECHLER | Jim DINE | Jean-Michel FOLON | Man RAY | Robert MOTHERWELL | James ROSENQUIST | Ed RUSCHA | Sean SCULLY | Kiki SMITH | Frank STELLA | Donald SULTAN | Roy LICHTENSTEIN | Hans HARTUNG | Arnulf RAINER | Georg BASELITZ | Claes OLDENBURG | Paul DELVAUX | Chuck CLOSE | Jasper JOHNS | David HOCKNEY | Thiebaud WAYNE | Jordi ALCARAZ | Joe TILSON | Gunther UECKER | James TURRELL | Ross BLECKNER | Francis BACON | Alexander CALDER | Howard HODGKIN | Yayoi KUSAMA | Antoni CLAVE | Tracey EMIN | Tony CRAGG | Peter DOIG | Carlos AMORALES | Lynda BENGLIS | José BEDIA | Massimo BARTOLINI | Michael CRAIG-MARTIN | Luis CAMNITZER | León FERRARI | Guillermo KUITCA | Marco MAGGI | Matt MULLICAN | Liliana PORTER | Laure PROUVOST | James SIENA | Xiaobai SU | Huai-Qing WANG | William ANASTASI | Roberto MATTA | Francois MORELLET | Antony GORMLEY | Jaume PLENSA | Piero DORAZIO | Karin KNEFFEL | Chris OFILI | Rosemarie TROCKEL | Manolo VALDéS | Glenn BROWN | Miquel BARCELó | Antonio DIAS | Joan HERNANDEZ PIJUAN | Francisca SUTIL | Tara DONOVAN | Rose WYLIE | Lucian FREUD | Eric FISCHL | Grayson PERRY | Joe BRADLEY | Stanley William HAYTER | Pol BURY | Alfons BORRELL | Albert RàFOLS-CASAMADA | Katia SANTIBAñEZ