What does the px unit mean?

What unit type is often the best and most powerful choice, especially for type?

When used for length measurement, what is a percentage unit a percentage of?

What is the default pixel equivalent for 1rem?

How can you change the size of 1rem?

True or False: It is generally better to use em units instead of rem units.

What unit of measurement is a percentage of the height of the browser window?

Using the following CSS: font-size: 200%, what would be the size of the type?