Display memory usage. Available only in 32 bit systems.
Syntax MEM MEM /C MEM /D MEM /P
/P List programs in memory with the memory address and size of each /D List Programs(as /P) and also Devices /C List programs in conventional memory and list programs in upper memory
MEM will only display details about the current CMD shell environment, programs running in a separate shell (or WIN32 programs) will not be listed - so it won't tell you anything about total memory usage.
“The palest ink is better than the sharpest memory” ~ Chinese proverb
MSINFO32 - Windows System Information.
MDSCHED - Windows Memory Diagnostic Scheduler.
GUI Task Manager - for all program details including Win32 applications.
TLIST - Task List.
powershell: gcim Win32_PhysicalMemory / gcim Win32_ComputerSystem
Q126962 - How to increase desktop heap memory for non-interactive processes.
Memory Management.doc - explains allocation of memory address space (Microsoft.com)
Equivalent bash command (Linux): free -t Display a summary of current memory usage and availability.