I use the “dd” command fairly frequently, to put new versions of SystemRescue on the USB stick I dedicate to that purpose, for example. The command has been nicknamed the “data destroyer”, because while doing sector-level copies as root, it can be all too easy to write to the wrong device, and destroy an important filesystem. The “lsblk” command can be handy for confirming which block device you should be writing to, before pressing Enter on that fateful command. There’s lots of information it can display, to help you identify the right device. For example, a command like lsblk -o NAME,SIZE,SERIAL,WWN,VENDOR,MODEL shows a little tree display of devices and partitions in the first column, followed by a lot of info you can use to identify what is currently plugged in. I tried a couple of USB sticks, and they showed amazingly long strings for their serial numbers. My SystemRescue stick shows the vendor as “TOSHIBA” and the model as “TransMemory”. Interestingly, both Western Digital and Seagate drives show the vendor as “ATA”, though the model name begins with “WDC” for the one and “ST” for the other. The SSD boot drives in both my main workstation and laptop display blank for the vendor, but again the model field shows some vendor-specific information.