merging two columns

Excel 2003

Good Morning or Afternoon as the case may be!

I'm working with a large dataset that has two columns that will need to be merged together.

Column A is first name
Columb B is last name.

I need a column that take A and B and merges them together seperating them by a space, resulting in text that look like "First Last"

Thanks for your time!
-Yak