IPFS is not a normal filesystem, such as fat32, ntfs, or ext3. It is more similar to Dropbox. It is a cross-device filesystem. You can save a file in this filesystem and people around the world can access it as easily as if the file were on their own computer. If Ethereum can be thought of as the world's singleton operating system, IPFS can be considered as the world's singleton storage!
The slogan of the IPFS website is IPFS is the Distributed Web. IPFS tries to replace, or at least supplement, HTTP. The HTTP protocol has served us for a long time, over 20 years, but it is not considered sufficient for upcoming challenges, such as increasing bandwidth demands or redundancy of files. HTTP uses a client-server model. You can only choose one of these two roles: either to be a server or a client.
There are a couple of problems with this architecture...