他 and 她 are both pronounced tā.

The individual symbols, known as radicals, have meaning, and they can be useful when trying to work out the meaning of an unfamiliar character. For example, given 也 means also, 人 means man and 女 means woman, you can guess that 他 means something like other man, 她 other woman. 子 means child; it is good for a mother and child to be together, therefor 好 means good. That being said, links like these can be tenuous at best- you're better off using a dictionary to make sure.