Hierarchy in typography is really important for making websites and apps easy to use. When typography is designed well, it helps users understand what information is the most important and how everything is organized on the screen. This is key to helping them find what they need quickly, making their experience better.

First, creating a clear typographical hierarchy means using different font sizes, weights, and styles. For example, headings are usually bigger and bolder than regular text. This helps users know where the important sections are. When the main topics are in larger font, it's easier for users to see what the page is about. On the other hand, smaller fonts can be used for less important information, helping users understand how different pieces of information relate to one another.

Also, using consistent typography helps with usability. When a design has the same font styles and sizes everywhere, users start to figure out how the information is laid out. This makes it easier for them to navigate without getting confused. For instance, if all buttons look the same, users can quickly spot them.

Whitespace is another big part of typographical hierarchy. Having enough space around the text keeps things from looking too crowded, which helps users focus better. This extra space not only makes reading easier but also guides users as they go through the content.

In summary, a clear typographical hierarchy in UI design helps users navigate better by showing how information is structured. This makes things easier for them to find and interact with what they need. Good typography is a key part of creating user-friendly websites and apps.