This background has abstract texture with some similarities to wood.
Source V. Hartikainen
Not a flat you live inside, like in the UK – but a flat piece of cardboard.
Source Appleshadow
A bit like some carbon, or knitted netting if you will.
Source Anna Litvinuk
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
A smooth mid-tone gray, or low contrast if you will, linen pattern.
Source Jordan Pittman
A white version of the very popular linen pattern.
Source Ant Ekşiler
Here I have tried to create something that would look like maple wood. Not sure how well it's turned out, but at least it looks like wood.
Source V. Hartikainen
Here's an yet another background for websites, with a seamless texture of wood planks this time.
Source V. Hartikainen
Inspired by an image that was uploaded to Pixabay by geralt
Source Firkin
Remixed from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
A bit like smudged paint or some sort of steel, here is scribble light.
Source Tegan Male
Dark and hard, just the way we like it. Embossed triangles makes a nice pattern.
Source Ivan Ginev
A free seamless texture of reptile skin colored in a dark brown color. As always, you may use it as a repeated background image in your web design works, or for any other purposes.
Source V. Hartikainen
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
I guess this one is inspired by an office. A dark office.
Source Andrés Rigo.
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
Thin lines, noise and texture creates this crisp dark denim pattern.
Source Marco Slooten
The classic subtle pattern. Sort of wall/brick looking. Or moon-looking?
Source Joel Klein
8 by 8 pixels, and just what the title says.
Source pixilated
Psychedelic Geometric Background No Black
Source GDJ
A hint of orange color, and some crossed and embossed lines.
Source Adam Anlauf
Plywood Web Background background image for use in web design.
Source V. Hartikainen
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Prismatic Hypnotic Pattern No Background
Source GDJ
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin