# How Rejarsume works

> A resume is one Markdown file drawn by a template, and the page you see is the document you export, which is why the PDF matches.

Three ideas explain most of how Rejarsume behaves. Once they are clear the rest of
these docs read as detail.

## A resume is a Markdown file

What you write is plain Markdown: your name, then sections, each a heading with
whatever follows it. A few extra lines, called directives, cover the parts
Markdown has no word for, such as a job with dates. The
[shape of the file](https://shopsalone.com/en/docs/format/overview.md) describes them.

The Markdown is the content. It says nothing about fonts, colours or margins, so
you can change how a resume looks without touching a word of it, and the other
way round.

## A template draws it

How the content looks comes from three layers, each applied over the one before:

- a template, which is the base look;
- the style settings, such as paper size, margins, fonts and colours;
- your own custom CSS, if you write any, which has the last word.

Because the layers are separate, switching template keeps your content and your
settings keep your tweaks. Your CSS can restyle the paper but cannot reach the
rest of the app.

## The page is the export

The preview is a real page, laid out at the real paper size. Rejarsume measures how
tall each block is and places whole blocks onto pages, so an entry is never cut
in half by a page break. The HTML export is that same page as one file, and the
PDF is that file printed, so the PDF and the preview are one document with two
destinations and neither can drift from the other.

The paper stays light even when the app is in a dark theme, because a printed
resume is white.

## Resumes and cover letters

A cover letter is the same kind of document: it lives in the same library, opens
in the same editor and exports the same way. It is written as paragraphs with no
section headings, and starts from a design suited to a letter. You make one from
the **New resume** dialog, or from a resume's menu in the library.

## What it is not

Rejarsume does not keep a history of every edit you make to a resume. Undo steps
back through recent changes, and a copy for one job is a separate resume you can
compare with the original. For a copy of everything, see
[Backup and restore](https://shopsalone.com/en/docs/data/backup-restore.md).