Editor's Note: This article has been updated by its author. Thank you, Pat. Have you ever wanted to change the names of many files at once? Or, have you ever needed to use a default value for a ...

Java’s String class encapsulates an array of bytes. A byte can be converted to a char, in which case, String becomes an array of characters used to compose words, sentences, or any other data you want ...

protect a variable name from surrounding characters. $ export foo=foo $ echo ${foo}bar # foo exists so this works as expected foobar $ echo $foobar # foobar doesn't ...