Your cooperation is needed for this project.

I need you.

This information is very important.

Do you understand the necessity of this project?

That information is unnecessary.

That information is completely unnecessary.

He thinks that war is a necessary evil.

I am majoring in information science.

Information retrieval technology is essential for finding necessary information from a large amount of data.

Information theory is a field of study that mathematically analyzes the amount of information and the efficiency of its transmission.