Daguerreotype
Invented by Louis-Jacques-Mandé Daguerre and introduced worldwide in 1839, daguerreotype was almost completely superseded by 1860 with new, less expensive processes yielding more readily viewable images. In the late 20th century, there was a revival of daguerreotypy by a small number of photographers interested in making artistic use of early photographic processes.
Post-mortem photography
The invention of the daguerreotype in 1839 made portraiture much more commonplace, as many of those who were unable to afford the commission of a painted portrait could afford to sit for a photography session. This cheaper and quicker method also provided the middle class with a means for memorializing dead loved ones.