This image gives a quick visual overview of different typographical terms

A few typography terms

Where type sits, it measures the vertical distance between text and an element.

Baseline

The height of a capital letter measured from the baseline. *a higher x-height makes the typeface more legible when smaller

Cap height

the height of lowercase of a typeface *the height of the typeface's lowercase x determines the x-height

X-height

Ascender - the height of letters that are above the cap-height or baseline Descender - letters stroke below the baseline

Ascenders and descenders

The thickness of a font's stroke.
The typeface can have between 4 to 6 weight types


Weight

Certain guidelines for the implementation of typefaces and fonts help create a balanced user interface. 

1- "Make sure that the header font and the body font gives the same impression to readers." The general message being delivered should reflect in both the header font and the body font.
2-"Don't combine two fonts from the same classification, but different families"
3-"Make clear differences in font weights". A bad implementation would give a weak weight to the header and a strong emphasis on the body text, which can confuse the user.


Guideline for Combining Typefaces

Typeface - design of a letter form

Font - a collection of typefaces

Picking a typeface for it's style, legibility, and readability are effective when following the fundamental principal of typographic design

DePaul University

Typography shows hierarchy and brand presence

Understanding Typography

Material Design Documentation

Type properties

"While legibility is determined by the characters in a typeface, readability refers to how easy it is to read words or blocks of text, which is affected by the style of a typeface."

Some properties that can affect readability: letter-spacing, line length, line height, paragraph spacing, type alignment and how figures are displayed (tabular or proportional).

Readability

"System fonts come pre-installed on your computer or device. They typically have wide language support and no licensing costs for developers. "

- Pros: consisteny with the platform, zero latency
- Cons: may not stand out

- Examples:
Roboto for Android, San Francisco for Apple, Fire Sans for Firefox OS, Segoe UI for Windows

- Pick a system font? 
https://practicaltypography.com/system-fonts.html#:~:text=System%20fonts%20are%20the%20fonts,system%20fonts%20aren't%20good.

System fonts

There are five categories of fonts: Serif, Sans Serif, Monospace, Handwriting, and Display. 

Type Classification

An article written by Spencer Mortensen introducing the history of the development of typographic scale and how designers should use them to make content readible and aesthetic.
- https://spencermortensen.com/articles/typographic-scale/

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