OpenGL Programming Guide: The Official Guide to Learning OpenGL, Version 4.3, Eighth Edition

Creating and Initializing Textures

The first step in using textures in OpenGL is to reserve names for texture objects and bind them to the context’s texture units. To create a texture, as with many other objects in OpenGL, names are reserved and then bound to their appropriate target. To reserve names for texture objects, call glGenTextures(), specifying the number of names to reserve and the address of an array into which to deposit the names.

void glGenTextures(GLsizei n, GLuint *textures);

Returns n currently unused names for texture objects in the array textures. The names returned in textures will not necessarily be a contiguous set of integers.

The names in textures are marked as used, but they acquire texture state and dimensionality ...