Background pattern 227 (colour 6) #2309
 Red  CC 0

A seamless background drawn in Paint.net and vectorised with Vector Magic. The starting point was a photograph of drinking straws from Pixabay.

Source Firkin

 More Textures
Foggy Birds #579
 Light  CC BY-SA 3.0

Hey, you never know when you’ll need a bird pattern, right?

Source Pete Fecteau

Groovepaper@2X #578
 Paper  CC BY-SA 3.0

With a name like this, it has to be hot. Diagonal lines in light shades.

Source Isaac

Colorful Geometric Pattern Background #231
 Noise  CC 0

PDP

Source GDJ

Repeating Website Background (Blue Gray) #1192
 Concrete  CC BY-SA 3.0

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

Vichy #71
 Light  CC BY-SA 3.0

This one could be the shirt of a golf player. Angled lines in different thicknesses.

Source Olivier Pineda

meshed silhouette-omnibus #2484
 Brown  CC 0

The image depicts meshed silhouettes of various things.The original image is an OCAL clipart called "Enter FOSSASIA 2016 #IoT T-shirt Design Contest" uploaded by "openclipart".Thanks.

Source Yamachem

Prismatic Dots Background 8 #515
 Noise  CC 0

Prismatic Dots Background 8

Source GDJ

Background pattern 223 (colour 4) #2350
 Pink  CC 0

Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.

Source Firkin

"Polished Stone", Gray Background Pattern #1053
 Stone  CC BY-SA 3.0

A seamless gray background texture suitable for use on websites. To me, it has the look of stone. Feel free to modify it to meet your needs (by making it a bit lighter or darker, for example).

Source V. Hartikainen