lhunath 1287148344 learn Curly-braces in parameter expansions are used when the parameter name is ambiguous: "${foo}bar", "${foo[1]}". They are not necessary for normal PEs (eg. "$foo"). They are no replacement for quoting. echo ${line} is BROKEN. (use echo "$line" or "${line}") ormaaj 1423925081 forget ormaaj 1423925089 learn Without curly braces parameter expansions refer to the longest valid variable name or shortest positional parameter. "${var}bar" expands the parameter named "var" while "$varbar" expands "varbar". "$123" references argv[1] and "${123}" references argv[123]. Braces are requried for parameters > 9, special PEs, and array expansions: ${10}, ${var##pat}, ${arr[5]}. BRACES AREN'T A SUBSTITUTE FOR QUOTES!