The image is a seamless pattern of a fishnet.
Source Yamachem
Prismatic Polka Dots Mark II 3 No Background
Source GDJ
Black brick wall pattern. Brick your site up!
Source Alex Parker
Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
Formed from decorative divider 184 in paint.net. Vectorised with Vector Magic.
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A seamless pattern based on a square tile that can be retrieved in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
Seamless Light Background Texture.
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
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
You may use it as is, or modify it as you like.
Source V. Hartikainen
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Prismatic Curved Diamond Pattern 3 No Background
Source GDJ
A new one called white wall, not by me this time.
Source Yuji Honzawa
Derived from elements found in a floral ornament drawing on Pixabay.
Source Firkin
From a drawing in 'Studies for Stories', Jean Ingelow, 1864.
Source Firkin
This one is rather fun and playful. The 2X could be used at 1X too!
Source Welsley
An abstract Background pattern of purple twisty patterns.
Source TikiGiki
Prismatic Abstract Line Art Pattern Background 2
Source GDJ
A seamless texture of black leather. I think it will look best when used in headers, footers or sidebars.
Source V. Hartikainen