Thanks for the details everyone.  Definitely helped

Thanks John.  This is good info but do we have a detailed breakdown of what files or folders are stored where?  I am trying to answer the below questions.  I believe storage is the MDOC and program is RAM?  I thought ECRT had a doc on this but I can't seem to find it for the MC75
Can you tell me what I am looking at under settings-> memory on the MC75?

IS this all on the DOC?

It shows storage 136M and Program 114M

Is this all available to us (or atleast what show as free)? 

The program side show 84M free.  Is that all reserved for the possibility of the OS growing or can I use that space?

Where does the application directory reside?  Is it under one of these two categories?  MDOC NAND

The Program area is RAM (memory used for running applications - executing code, heaps, and stacks).  To use it for file storage you can create (or increase the size of) the CacheDisk. The Storage area is mdoc flash memory, specifically the primary filestore (ie: \ filesystem). This memory can be used by placing files in any directory that is not a mount point for a different file store (ie: \Application, \CacheDisk, \Storage Card - if an SD card is insterted).

The total storage space refers to the amount of the MDOC reserved for the persistent store.  So yes the storage space is all on MDOC and it what is left after allocating space for the OS and Application partitions.  The persistent store includes all files off the root except \application and \cache disk.  You are free to use the remainder of this and you will use it by placing files in any folder like \program files and \temp. From your example you probably have a 256MB flash unit so its 256 - OS - App and you are left with ~136 to use for the root filesystem. Program memory refers to the amount of physical RAM remaining in the system after what is reserved for the OS.  If you show 114MB available you probably have a 128MB unit.  84MB is left after what is being used by currently running applications.  The rest is available to start up more apps or for further allocations in current apps.  Keep in mind that this is physical ram and in ce5/wm6.5 we are still limited to 32MB virtual memory for each process. John

The MDOC is used as the flash controller for all the flash and is not it any way, assocoiated with the RAM. The MC75 uses only NAND Flash: NOR flash is not used. The RAM area is used for several purposes: 1. To execute programs. 2. As a temporary storage for those data that is considered critical and needs the performance characteristics of writing to RAM. 3. As a cache for the file system. All file system write operations, unless overridden by cache writethrough (defaulted to OFF in the MC75), are written to a RAM area where the file data is then 'flushed' to the intended file when the file is closed, a flush command is issued, during a WARM boot or the OS has time to flush this cache (lazy write). Note that when the cache is flushed, if multiple file data is present in the cache, then all that data is flushed: it is not possbile to flush only on file's data. 

The MDOC is used as the flash controller for all the flash and is not it any way, assocoiated with the RAM. The MC75 uses only NAND Flash: NOR flash is not used. The RAM area is used for several purposes: 1. To execute programs. 2. As a temporary storage for those data that is considered critical and needs the performance characteristics of writing to RAM. 3. As a cache for the file system. All file system write operations, unless overridden by cache writethrough (defaulted to OFF in the MC75), are written to a RAM area where the file data is then 'flushed' to the intended file when the file is closed, a flush command is issued, during a WARM boot or the OS has time to flush this cache (lazy write). Note that when the cache is flushed, if multiple file data is present in the cache, then all that data is flushed to the intended files: it is not possbile to flush only one file's data. 

Thanks for the info, Is the MDOC chip the NAND, RAM or both?

I dont know what the MDOC chip is..I would assume it is in one or the other (not both) since there are different components for RAM(not persistent)  and NAND(persistent)

The MDOC is used as the flash controller for all the flash and is not it any way, assocoiated with the RAM. The MC75 uses only NAND Flash: NOR flash is not used. The RAM area is used for several purposes: 1. To execute programs. 2. As a temporary storage for those data that is considered critical and needs the performance characteristics of writinf to RAM. 3. As a cache for the file system. All file system write operations, unless overridden by cache writethrough (defaulted to OFF in the MC75) are written to a RAM area where the file data is then 'flushed' to the intended file when the file is closed, a flush command is issued, the OS has some time to flush this cache (lazy write) or during a WARM boot. Note that when the cache is flushed, if multiple file data is present in the cache, then all that data is flushed: it is not possbile to flush only on file's data. 

Here is a doc I created with the help of Tier 3 support. Its pretty generic, but I think it contains the info customers typically want. When you look at the memory tab, the Storage indicates the available NAND memory, and the Program Memory represents RAMPlease let me know of you have questions