Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
The act or state of corrugating or of being corrugated, a wrinkle; fold; furrow; ridge.
Source Anna Litvinuk
From a drawing in 'Gately's World's Progress', Charles Beale, 1886.
Source Firkin
A dark gray, sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
Remixed from an image that was uploaded to Pixabay by Pixeline
Source Firkin
Clover with background for St. Patrick's Day. Add to a card with a doily, ribbon, a leprechaun or other embellishments.
Source BAJ
Remixed from a design seen on Pixabay. The basic tile can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Prismatic Groovy Concentric Background 5 No Black
Source GDJ
Remixed from a design on Pixabay. To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Medium gray pattern with small strokes to give a weave effect.
Source Catherine
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
To get the tile this is formed from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Looks like an old wall. I guess that’s it then?
Source Viahorizon
A slightly grainy paper pattern with small horizontal and vertical strokes.
Source Atle Mo
Same as Silver Scales, but in black. Turn your site into a dragon with this great scale pattern.
Source Alex Parker
The following repeating website background is colored in a blue gray color and resembles a concrete wall or something similar to it.
Source V. Hartikainen
Inspired by a pattern seen on a public domain image of a very old tile. To get the unit cell, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
Seamless Background For Websites. It has a texture similar to cork-board.
Source V. Hartikainen
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Prismatic Isometric Cube Wireframe Pattern No Background
Source GDJ
This is a seamless pattern of a woody texture.The original image is here:https://pixabay.com/ja/users/ClassicallyPrinted-1302233/
Source Yamachem
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
This ladies and gentlemen, is texturetastic! Love it.
Source Adam Pickering
Submitted by DomainsInfo – wtf, right? But hey, a free pattern.
Source DomainsInfo
Prismatic Groovy Concentric Background 5
Source GDJ