COM files are similar to binfiles.

I think the COM file only has one more tag than the binfile: org 0100 H, telling you that this file is dedicated to dos.

Both are executableProgramMemory image file: the so-called image, that is, to load the binfile or com file on the hard disk back into the memory, and then set the Cs: IP point to the First Command of the file, the CPU can run smoothly.

 

They only have the basic elements of the program: commands and data.
When dos executes the COM file, it will first create a byte PSP memory space (used to communicate with the com Program), four segment registers all point to PSP, and then load the COM file to CS: 100h. DOS uses Cs: H as the program entry.
The binfile is used only during system boot. It seems to be more underlying.
Related Articles Article, Text is very accurate: http://blog.sina.com.cn/s/blog_7321b86701011uxa.html