Textures.com - Textures.com is a website that offers digital pictures of all sorts of materials.
Texturefun - Texturefun is software that offers high-quality textures in every size, making you download and use any texture in your 3D or 2D models.
Poly Haven - Poly Haven (formerly known as Texture Haven) is an online website where you will find scanned textures without any cost and that are of high quality.
Seamless PBR Textures - Seamless PBR Textures is one of the intelligent software that utilizes physically based rendering technology that aims to simulate when light reacts with the model.
Poliigon - A library of materials, and HDR's for artists including free textures that want photorealism.
3DExport CG Textures - 3DExport CG Textures is an online store that provides you an opportunity to buy or sell 3D models, textures, plugins, and digital prints.