This is the 131st most frequent Russian word.
надо
"Надо" means "it is necessary" or "one must."
Here, 'надо' is used to indicate necessity or obligation.
Мне надо купить хлеб.
I need to buy bread.
In this sentence, 'надо' conveys a recommendation or suggestion.
Тебе надо почитать эту книгу.
You should read this book.
This usage of 'надо' states a lack of necessity for an action.