Dare I call this a «flat pattern»? Probably not.
Source Dax Kieran
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
The act or state of corrugating or of being corrugated, a wrinkle; fold; furrow; ridge.
Source Anna Litvinuk
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
From a drawing in 'Les Chroniqueurs de l'Histoire de France depuis les origines jusqu'au XVIe siècle', Henriette Witt, 1884.
Source Firkin
Derived from a PNG that was uploaded to Pixabay by nutkitten
Source Firkin
The tile this is based on can be retrieved by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
A background pattern with green vertical stripes. A new striped background pattern. This time a green one.
Source V. Hartikainen
Smooth Polaroid pattern with a light blue tint.
Source Daniel Beaton
A fun-looking elastoplast/band-aid pattern. A hint of orange tone in this one.
Source Josh Green
A seamless pattern recreated from an image on Pixabay. It is reminiscent of parquet flooring and is formed from a square tile, which can be recovered in Inkscape by selecting the ungrouped rectangle and using shift-alt-I together.
Source Firkin
Sharp diamond pattern. A small 24x18px tile.
Source Tom Neal
You know I love paper patterns. Here is one from Stephen. Say thank you!
Source Stephen Gilbert
A repeating background with wood/straw like texture.
Source V. Hartikainen
Derived from an image that was uploaded to Pixabay by mdmelo.
Source Firkin
Prismatic Abstract Background Design
Source GDJ
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
Classic vertical lines, in all its subtlety.
Source Cody L
From a drawing in 'Cowdray: the history of a great English House', Julia Roundell, 1884.
Source Firkin
Some dark 45 degree angles creating a nice pattern. Huge.
Source Dark Sharp Edges
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
Love me some light mesh on a Monday. Sharp.
Source Wilmotte Bastien
I guess this one is inspired by an office. A dark office.
Source Andrés Rigo.