Extended Memory
Above the 1-MB boundary. Early IBM personal computers could
not use memory above 1 MB, but current PCs and their software
can use extended memory.
Other Memory
Between 640 KB and 1 MB; often called High memory. DOS may
load, terminate-and-stay-resident (TSR) programs, such as device
drivers, in this area, to free as much conventional memory as
possible for applications. Lines in your CONFIG.SYS file that start
with LOADHIGH, load programs into high memory.