Smart Phone Flash tool (SP Flash tool) was developed by Mediatek Inc. Its a tool for flashing and dumping (backing up) Mediatek (MTK) devices. It will only work on Mediatek devices (smartphones, tablets, smartwatches, GPS etc).
How to flash using SP Flash tool
SP Flash tool requires a scatter file (.txt) and the firmware (or at least one file) you wish to flash. For ease, its best to have the scatter file and file(s) to be flashed in the same folder. After loading the scatter file, the files to be flashed should be automatically loaded. Once SP flash is set to flash, you simply power off and connect the device to the PC via a USB cable. You mostly don't need to hold any button on the device to get into Flash Mode.
Here's a detailed guide on how to use SP Flash tool
Formatting is used to fix extreme software issues or force-flash in SP Flash tool; however, its a flash option I suggest you rarely use. The reason is that you could end up with dead boot, null IMEI or sensor issues. In addition to this, formatting a Secure Boot device will make it request an Authentication (auth) file for subsequent flashes.
SP Flash tool; DA / Auth files and Secure Boot devices
Secure Boot is one security features more Mediatek devices are adopting. Flashing such devices requires a unique Download Agent (DA) file, maybe an auth file and factory / signed firmware. Flashing a backup (made from another device of the same model) tends to brick Secure Boot devices.
DA, Auth. and Factory / Signed firmware are sourced from the device manufacturer. We have a collection here so check for your model.