Rows and Swimlanes

Rows - known colloquially as swimlanes - are used to break up the tasks on the board in one of several ways; however makes sense for the particular type of board.

Kanboard User Docs

Setup

Configure this project

Go to the "Swimlanes" section

Add, delete or edit a swimlane:

Configuration

There are a couple of rules of thumb when it comes to swimlanes. Use these to indicate priority, with the higher priority towards the top. Don't use these to split up tasks by Assignee - that's what the assignees and filters are for. 

Here is the most basic swimlane setup, from top to bottom:

1. Critical
2. Everything Else

Here is a bit more granular setup with four swimlanes that breaks repetative work into a "Maintenance" swimlane, and splits up "nice to have's" into a column called "Improvements", and bugs/issues/problems into another swimlane called "Incidents".

1. Critical
2. Incidents
3. Maintenance
4. Improvements

Similarly to the most basic setup, you can categorize your swimlanes by visibility:

1. External Projects
2. Internal Projects

This setup is intended to be worked from top to bottom, with tasks moving from the last column of the higher swimlane into the first column of the lower swimlane:

1. Onboarding
2. Initial Review
3. Ongoing Touchbases

Swimlanes are the most efficient way to categorize tasks on a board according to priority or type of task, but I would caution against using them to indicate things that other aspects of the task are meant to indicate (See: Categories, Due Dates, etc.)