TYPOGRAPHY

The main purpose of Graphic Design is to convey a message in an easy, effective and appealing way.  Usually, although not always, the message is transmitted via text.  
This is when words become design elements.
Not only they need to be clearly legible, but they have to work in harmony with the other elements in the composition. Sometimes making words not so legible could also be a design and creative choice.
Having the knowledge on how to manipulate text helps us reinforce, for example, a brand identity.
Words can be beautiful too and they have the power to transmit their own message independent of the message they are conveying. 

Proper use of typography not only has the ability to communicate a message but we can tweak it to establish visual hierarchy, harmony, balance, and a visual path to navigate our composition. 

The use of a specific font in a specific way can lock in a brand perception, through-for example- a logo or a packaging aesthetic.  It is the visual tone of voice with which a corporation talks to its audience. 

Typography refers to the way in which we style and arrange type.  It includes decisions on typeface, font, size, weight, alignment, spacing, etc.  It's not just the selection of a font, of series or fonts. This is only one aspect of typography.  

Typeface is a particular style of lettering. 
This could include, for example, whether a letter has serifs (stroke at the end of the letterform), as well as the shapes and forms of it's different elements. 
Going into the Anatomy of a typeface, this could include the characteristics of it's different components, such as tails, brackets, Cap and x- heights, etc. 

Font refers more to what typeface we have chosen.
There's also different characteristics within a same font, such as bold or italic for example.  But we can also add weight and size. 

Theres's 3 basic typefaces: serif, sans-serif and script. 

Serif features a decorative line or "flick" at the end of the main strokes of different characters.  Amongst the most known serif fonts we find Times New Roman (which is the font I'm using). As an example, we can see the extra strokes embellishing the "T"s.

Sans Serif as you can deduce, means with no extra strokes. They tend to look more modern and are easier to read. 

Script mimics handwriting and makes us think of calligraphy. Since they are harder to read, they are mostly used as decorative elements.  I also believe that our eyes have strayed away from reading these types of fonts.  I learned how to write before computers were a thing. We were taught calligraphy and how to hand write and read in cursive.  Our eyes were more adjusted to this type of reading.
As technology evolved and our written lives changed,  typed fonts on phones and other screens became the norm and our eyes lost some of that training.   I used to work at an Apothecary. We sold herbs by the oz that we would bag in a recyclable paper bag. We had to write on pencil the name of the herb and below the instructions. I used to write the name in cursive. I believed it looked "cute" and soft.  I was surprised when some young kids called the store asking what they said, because they couldn't read cursive.  Especially characters like capital "S", "G" or "H".   This thought on education made me sad. But that's a whole different discussion !

One of my favorite fonts is Helvetica.

It is a Sans-Serif typeface developed in 1957 by Swiss typeface designer Max Miedinger and Eduard Hoffmann. 

It is very powerful and easy to read. The x-height is taller than your usual font and the spacing is relatively tighter which gives it a bolder or rather more solid look. 

It is such a recognizable font that it caused a bit of a funny incident when the sign installer mistakenly used Helvetica Black instead of the usual Helvetica Bold for certain Washington Metro stations (WMATA). This created an enraged and comical discussion amongst design oriented metro users that lead to apologies and re-dos from that department. 

As a fun fact LA Metro uses DIN Engschrift