@Helix no but you program it like one given that you're programming many, many, many small nodes with on-board memory that interconnect. The usual boxes that embedded ticks - weird memory management, no/limited file system, limited resources, weird networking - all apply here.
Managing going in and out of low power states?
Coding for low power?
Squeezing computation out of a strict number of cycles?
Squeeze code into smaller flash memory?
Severe memory shortage?
Devices designed to execute for a number of years without a reboot?
Code written to safety integrity levels?
No networking, gui, output streams etc?
Highly expensive or impossible to change code once deployed?
Apart from that just the same.