It means hat the CPU is taking o much of what the phone can normally do try delete some apps or close apps your not using
It's usually called "Booting Up"
Booting up is usually the process in which you usually refers to the computer loading up basic software to the computers memory.
An at-risk driver is someone who is recklessly driving. an at-risk driver is a driver who is driving at a very high rate of speed. an at-risk driver is a driver who is someone who is driving in dangerous way as in no seatbelt or being distracted.