OEM character sets (Original Equipment Manufacturer). The 8th bit often contained characters for line drawings as a carry over from pre-GUI (Graphics User Interface) days. Different countries or companies did whatever they wanted with that 8th bit. Used by DOS, OS/2, floppy disks, and the FAT system (File Allocation System).
In Windows you can use the
chcp [nnn] command to display or set the active code page number.
Aka: CP437, OEM 437, PC-8, MS-DOS Latin US, OEM font, High ASCII, Extended ASCII.
Used in IBM DOS, OS/2, and MS-DOS. Codes 32-126 are teh same as ASCII. 437 is often the default active code page. Keyboard shortcut: Alt+#, EG:
Alt+21 enters the section sign
Aka: 850 Multilingual.
850 is Microsoft's "improvement" on 437. Some of the line drawing characters since the world was becoming GUI.
Used in MS DOS.