freesewing/markdown/dev/guides/prerequisites/en.md

---
title: Before you start
order: 100
for: developers
icons: 
  - start
  - pattern
about: |
  A guide to go over a few things you should know when you start working with our core library
goals:
  - Understand that FreeSewing provides parametric pattern design
  - Understand that FreeSewing uses SVG
  - Understand the coordinate system
  - Learn that we use millimeter internally
  - Learn about Bézier curves
---

Drawing lines and curves on paper is a skill most people have been practicing since kindergarten.
In FreeSewing, we draw lines and curves with code, which is a bit more abstract
but doesn't have to be complicated once you understand a few basic building blocks.

Understanding the concepts that are involved in designing sewing patterns in code will pay dividents later.
That is why we recommend you familiarize yourself with the following topics:

<ReadMore list />

<Note>

##### There's no need to know everything

FreeSewing sits at the intersection of the world of makers and developers.
If your background is in development, you will need no explaining what SVG is, but might not
know much about designing sewing patterns.
If on the other hand your background is in sewing or pattern design, you might wonder what
the heck Node JS is and why you should care.

Few people straddle both worlds, so as you start using FreeSewing, chances are
you'll learn a few new things along the way.

</Note>