Version-Control

Two parent commits connected to a reviewed merge result.

Git merge joins two diverged lines at a new commit

A merge connects histories and records a resulting project snapshot. In an ordinary merge of two diverged branches, the new commit names both prior tips as parents. Those parent links keep the earlier commits reachable, but they do not prove that the resulting files retain every intended behavior. Merging is both a graph operation and a content decision; verifying only one of those aspects leaves important mistakes undetected. ...

A lightweight pointer that labels one commit inside the history graph.

A git branch is a moving label on a commit

A Git branch names the tip of a line of history. Creating another branch normally adds a reference to an existing commit, not another copy of every tracked file. Two names can point to the same commit and later advance independently. This makes branches inexpensive to create, but it does not mean their names contain the history or that deleting every reference to a commit is harmless. ...