PC/MS DOS
In the DOS era overlays were popular because the operating system and many of the computer systems it ran on lacked virtual memory and had very little RAM by current standards — the original PC had between 16K and 64K depending on configuration. "Several DOS linkers in the 1980s supported in a form nearly identical to that used 25 years earlier on mainframe computers." Binary files containing memory overlays had a defacto standard extension, .OVL. This file type was used among others by WordStar and dBase. The GFA BASIC compiler was able to produce .OVL files.
Read more about this topic: Overlay (programming)
Famous quotes containing the word dos:
“We’re headed for collapse, if you want my opinion, Missy. I can see it in the fallin’ off of the quality of vagrants. There was a time you could find real good company in almost any jungle you’d pick, men who could talk, men who’d read a book now and then; and now, what do you find, a lot of dirty little guttersnipes no decent tramp would want to associate with.
Well, it’s been that way all through history.”
—John Dos Passos (1896–1970)