[lammps-users] What it the meaning of this command

Here are the two successive commands in the example. I look through the manual, but cannot understand what is the meaning of “temp new” and why it should be set here?

compute new mobile temp
velocity mobile create 0.2 482748 temp new

I am sorry, I looked at the manual many times, but it seems complicated in the manual. Can someone rephrase the meaning of the manual in page534?

The compute sets up a calculation that computes the T of just a subset
of atoms (mobile).
The velocity command sets the velocity for those atoms.