Desu? Why do we use this??

[Ceciliaracia]

What does desu mean? and why it is it used??
Plz and thank you smile  

[blasted by bubbles]

"desu" really has multiple meanings. in general though it can mean, "it is." in japanese, there are no "subjects" like "i," "it," & "my major."

for example:
juuniji han desu literally translated would be, 12:30 (it is).
gakusei desu literally translated would be, student (i am a).
nihongo desu literally translated would be, japanese (my major is).


you could also use desu to identify a person or a thing X as item Y by using this structure; X wa Y desu.

for example:
watashi wa rumiko desu would be, i am rumiko.  

[yukikuro ame]

It's a state of being verb. Anytime you want to describe something, (that car is red), tell something about yourself, (I am American), or anything like that, you use desu.  

[Nana Shinu Ai]

domo ariagato explain it.
Watashi wa Emiko desu.  

[Nana Shinu Ai]

I think desu is former way of introducing yourself and action.  

[Nana Shinu Ai]

But if you want to learn more of it start on the Japanese lessons on the Sub forums.