You can open or create artwork and use this artwork as a fill pattern for objects or even text. Fill patterns can be created from line art, but also from pixel images.
How to create a fill pattern
1. Select the object(s) you want to use as pattern and click Extra > Create Pattern.
2. Click Window > Color to display the Color panel.
3. The pattern you created in step 1 is added to the Color panel (A).
4. Click Window > Color List.
5. Point to the pattern in the Color panel and drag it to the Color List.
The pattern can be applied to objects by drag & drop.
6. Click the menu button and select Save.