What are DOS memory settings?

The commands in this file configure DOS for use with devices and applications in the system. The commands also set up the memory managers in the system. After processing the CONFIG.SYS file, DOS proceeds to load and execute the command shell specified in the shell= line of CONFIG.SYS, or COMMAND.COM if there is no such line. The command shell in turn is responsible for processing the AUTOEXEC.BAT file.