Kvm Installation & Prerequisite

egrep -c '(vmx|svm)' /proc/cpuinfo

This searches if one of those two flags exist in the /proc/cpuinfo file.

SVM is flag related to the AMD virtualization (AMD-V). The CPU flag for AMD-V is "svm".

VMX is falg related to the Intel virtualization (VT-x). The CPU flag for VT-x capability is "vmx";

man egrep

NAME
       grep, egrep, fgrep, rgrep - print lines matching a pattern


DESCRIPTION
       grep  searches the named input FILEs (or standard input if no files are
       named, or if a single hyphen-minus (-) is given as file name) for lines
       containing  a  match to the given PATTERN.  By default, grep prints the
       matching lines.

       In  addition,  three  variant  programs  egrep,  fgrep  and  rgrep  are
       available.   egrep  is  the  same  as  grep -E.

then egrep is same as gerp -E which means also from man grep

 -E, --extended-regexp
          Interpret  PATTERN  as  an extended regular expression 

So in conclusion this will search the file /proc/cpuinfo for those cpu flags and then count the occurrence instead of printing the matching it counts matching number.

  -c, --count
              Suppress normal output; instead print a count of matching  lines
              for  each  input  file.