These are some characteristis of tlt:

• Tlt is a perl script, thus it is OS-independent.
• Allows non-interactive operation:

  	[foo@mortadelo /foo]# echo "Hello" | tlt
  	Hola
  

  And interactive mode:

  	[foo@mortadelo /foo]# tlt -i
  	Interactive mode. Write your text and press RETURN to translate.
  	Type CTRL-C when done.
  
  	hello
  	hola
  

• By default it translates from english to spanish. Its default behaviour can be changed by two ways:
  1. Using the -l or --lang option. For example, tlt -l ru_en translates from russian to english (tlt --help shows the full list of translation pairs).
  2. Using the environment variable TLTLANG. For example, if TLTLANG is equal to "es_en", tlt translates from spanish to english.
• It allows cross translations to translate between unpaired languages, for example, there is not de_es option (from german to spanish), but we can do the following:

  	[foo@mortadelo /foo]# echo "Nein" | tlt -l de_en | tlt -l en_es
  	No