The DOS executable header contains relocation information, which allows multiple segments to be loaded at arbitrary memory addresses, and it supports executables larger than 64k; however, the format still requires relatively low memory limits.
The DOS 2.x API introduced a new program termination function, INT 21h Function 4Ch which does not require saving the PSP segment address at the start of the program, and Microsoft advised against the use of the older DOS 1.x method.
32-bit Windows NT-based operating systems can execute them using their built-in Virtual DOS machine (although some graphics modes are unsupported).
Alternative ways to run these executables include DOSBox and DOSEMU.
MZ DOS executables can be created by linkers, like Digital Mars Optlink, MS linker, VALX or Open Watcom's WLINK; additionally, FASM can create them directly.