linux concatenate strings code example

Example 1: combine strings bash

foo="Hello"
foo="${foo} World"
echo "${foo}"
> Hello World

Example 2: sh concat string

VAR1="Hello,"
VAR2=" World"
VAR3="$VAR1$VAR2"
echo "$VAR3"

Example 3: bash variable in string

${!var}	#Just use to use reference value inside another variable ;)