If this is your first time encountering shorthand then you're in for a treat. What's shorthand? Shorthand is a technique for writing very quickly.

At its basics you're writing sounds not spelling and combining simple lines to make full words.

Get it? You're optimizing for speed of writing not density or accuracy. So it's hard to read and takes up more space but you can write down notes fast. How fast? Here's someone writing at 120 words per minute.

The world record is 250 wpm, but even with a little practice you can get a lot faster than cursive or print.

I've seen a few people ask if Jonathan is writing assuming Dracula can't read his notes. I don't know the answer to that, but I can share exactly that happening with Superman and Lex Luthor.

Naturally a reporter like Kent would use shorthand to quickly transcribe notes in the field.

This is the sort of think Mina is practicing specifically because it's the language used in business. You can read a great article on the expectations of men's and women's writing of the era here:

-ddx for differential diagnosis , rx for prescription, abx -antibiotics

bd- twice daily , PO = by mouth, NAD = no abnormalities detected