What does “the need of the hour” mean?

I came across this idiom in a title, in association with a noun:

[noun of a product category] — The need of the hour

What does this mean?

 

“Of the hour” is an expression used to indicate “of the present (short) period”:

  • Man of the hour
  • Need of the hour
  • etc (?)

It doesn’t literally mean an hour, but it does imply a short period of time.