How to read a Git log graph

The asterisks show where something was committed:

e1193f8, 5a09431 and 30e367c were committed to the left branch (yielding a | on the right branch) whereas 420eac9 was committed to the right branch (yielding a | on the left branch). And that is how 420eac9 differs from the rest: it’s the only commit to the right branch.

For the sake of completeness:

• d6016bc was the branching point
• 5e3ee11 is the merging commit
• 2d3acf9 is the first commit after merging