Dark and hard, just the way we like it. Embossed triangles makes a nice pattern.
Source Ivan Ginev
Formed by heavily distorting part of a an image of a fish uploaded to Pixabay by GLady
Source Firkin
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Detailed but still subtle and quite original. Lovely gray shades.
Source Kim Ruddock
Not even 1kb, but very stylish. Gray thin lines.
Source Struck Axiom
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Prismatic Abstract Geometric Background 3
Source GDJ
Pass parameters to the URL or edit the source code variables to configure the graph paper for the division desired.
Source JayNick
This background pattern has futuristic look. So, maybe it could be used on websites or blogs dedicated to video games?!
Source V. Hartikainen
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Floral patterns will never go out of style, so enjoy this one.
Source Lasma
A version without colours blended together to give a different look.
Source Firkin
Background Wall, Art Abstract, Block Well & CC0 texture.
Source Ractapopulous
A seamless texture of black leather. I think it will look best when used in headers, footers or sidebars.
Source V. Hartikainen
Neat little photography icon pattern.
Source Hossam Elbialy
Prismatic Geometric Tessellation Pattern No Background
Source GDJ
Zero CC tileable bark texture, photographed and made by me. CC0
Source Sojan Janso
Used correctly, this could be nice. Used in a bad way, all hell will break loose.
Source Atle Mo
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin