what does "cat > /sbin/reboot <<EOF" do in init script?

this is the init script from a ramdisk image.
After kernel finishes booting, it executes this init script.
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/bin/busybox --install -s

rm /sbin/reboot
cat > /sbin/reboot <<EOF
#/bin/sh

exec /bin/busybox reboot -f
EOF
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I think when this script is run, the initrd has been already mounted. What does "cat > /sbin/reboot <<EOF" do?