Why do we need Databases?

Have you ever wondered why we need databases when we can store data directly on an SSD? I recently asked myself this question. After all, SSDs store data permanently. If we can read and write directly to disk, why don’t we use that for building web applications and systems? At first, I thought maybe it’s because most applications use in-memory computation — in simple terms, RAM. When an application crashes, all data stored in RAM is lost. This creates reliability issues. So then I wondered: if persistence is our goal, why not write everything directly to the SSD? But then I realized something important — an SSD only provides physical storage. It does not provide data management. SSDs do not provide indexing, concurrent updates, or crash recovery. Implementing these manually on top of raw file storage would be extremely complex. Databases abstract this complexity and handle data efficiently. Now that we understand why databases exist, the next question becomes — what type of database sh