This Dictionary includes 1 CD, you should install the CD on your PC and than use it; it says the meaning of the words and the expressions and gives you some example of them; it also has Grammar part and explain some thing with the best illustrations.(NAME: Oxford)

This Dictionary includes 2 CDs, you should install the CDs on your PC and than use it; it says the meaning of the words and the expressions and gives you some example of them.(NAME: Longman Contemporary English)

This Dictionary includes over 4000 Idioms, it doesn't have any CD.(NAME: Longman AMERICAN Idioms DICTIONARY)

This Dictionary is a Handy Dictionary and you can use it wherever you want.(NAME: Longman Handy LEARNER'S DICTIONARY)