Here is a list of all topics with brief descriptions:

Library initialization	API elements related to the initialization and management of the entire library, especially VmaAllocator object
Memory allocation	API elements related to the allocation, deallocation, and management of Vulkan memory, buffers, images. Most basic ones being: vmaCreateBuffer(), vmaCreateImage()
Virtual allocator	API elements related to the mechanism of Virtual allocator - using the core allocation algorithm for user-defined purpose without allocating any real GPU memory
Statistics	API elements that query current status of the allocator, from memory usage, budget, to full dump of the internal state in JSON format. See documentation chapter: Statistics