This beige background pattern resembles a concrete wall with engravings or something similar to it.
Source V. Hartikainen
Zero CC tileable hard cover cells book texture, 4k, scanned and made by me. CC0
Source Sojan Janso
A slightly grainy paper pattern with small horizontal and vertical strokes.
Source Atle Mo
Everyone loves a diamond, right? Make your site sparkle.
Source AJ Troxell
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-i
Source Firkin
This ladies and gentlemen, is texturetastic! Love it.
Source Adam Pickering
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
To get the tile this is formed from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Here's a dark background pattern that contains a steel grid pattern as a texture. Use it as a website background or for other purposes. It's free!
Source V. Hartikainen
These dots are already worn for you, so you don’t have to.
Source Matt McDaniel
Here's an yet another background for websites, with a seamless texture of wood planks this time.
Source V. Hartikainen
A pattern derived from repeating unit cells each derived from part of a fractal rendering in paint.net.
Source Firkin
Abstract Geometric Monochrome Pattern Prismatic No Background
Source GDJ
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
Based on an image that was uploaded to Pixabay by devanath
Source Firkin
The classic notebook paper with horizontal stripes.
Source Are Sundnes
Prismatic Triangular Seamless Pattern III With Background
Source GDJ
Subtle scratches on a light gray background.
Source Andrey Ovcharov
This is so subtle: We’re talking 1% opacity. Get your squint on!
Source Atle Mo
A bit simplified version. Although it could be edited out to be simpler. Anyway, this time the tiling is converted to a pattern fill -which is using clipping for the tile's edges.
Source Lazur URH
A blue background wallpaper for websites. It has a seamless texture with vertical stripes. It looks quite nice not only when using as a tiled background on websites, but also on computer desktops.
Source V. Hartikainen