Major branches in the tree of language reconstructed
The diversity of human languages can be likened to branches on a tree. If you're reading this in English, you're on a branch that traces back to a common ancestor with Scots, which traces back to a more distant ancestor that split off into German and Dutch. Moving further in, there's the European branch that gave rise to Germanic; Celtic; Albanian; the Slavic languages; the Romance languages like Italian and Spanish; Armenian; Baltic; and Hellenic Greek. Before this branch, and some 5,000 years into human history, there's Indo-European -- a major proto-language that split into the European branch on one side, and on the other, the Indo-Iranian ancestor of modern Persian, Nepali, Bengali, Hindi, and many more.