terminal - what is the use of parentheses in linux command -


i run following command in linux terminal. can tell me use of parentheses in linux terminal , following command ?

$(echo "get / http/1.0";echo "host: www.google.com"; echo) | nc www.google.com 80

( list )
placing list of commands between parentheses causes subshell environment created, , each of commands in list executed in subshell. since list executed in subshell, variable assignments not remain in effect after subshell completes.


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