Do I need to unmount the OS SD card and mount a new one or will the same SD Card can be used further for storage of data purpose?? Kindly provide me with the details of stack (whether it is inbuilt or not)
The SD card in a Pi is the equivalent of the hard disk in a PC.
The SD card contains two partitions
- a partition with the files needed for boot formatted as FAT (so it's readable from a PC)
- a partition used to store the operating system and application programs and any files you create. This is formatted as ext4 which is not readable by a Windows PC (although you can get add on software which will read/write ext4 format).