ibm introduced eight-bit extended ascii codes on the original ibm pc and later produced variations for different languages and cultures. ibm called such character sets "code pages" and assigned numbers to both those they themselves invented as well as many invented and used by other manufacturers. accordingly, character sets are very often indicated by their ibm code page number. in ascii-compatible code pages, the lower 128 characters maintained their standard us-ascii values, and different pages (or sets of characters) could be made available in the upper 128 characters. dos computers built for the north american market, for example, used code page 437, which included accented characters needed for french, german, and a few other european languages, as well as some graphical line-drawing characters. the larger character set made it possible to create documents in a combination of languages such as english and french (though french computers usually use code page 850), but not, for example, in english and greek (which required code page 737).