panel 1: combining different versions of files is core to git

Illustration showing two boxes, each with three symbols, being added together.

(a, b, y) + (x, b, c) = ???

it’s very hard

panel 2: to merge files, you need to know what the original was

picture:

original is (a, b, c)

one side changed a -> x so it’s (x, b, c)

the other side changed c -> y so it’s (a, b, y)

panel 3: git merges by combining all changes

merge machine with everything from panel 1 in a thought bubble:

(a, b, c) (x, b, c) (a, b, y)

result is (x, b, y)

panel 4: if both changed the same line it’s a merge conflict

merge machine with a thought bubble showing:
(a, b, c) (x, b, c) (z, b, y)

result is (a/z, b, y)

The result has red question marks around it because the first position has two values in conflict. There are also red sad faces and x’s around the illustration.

panel 5: git figures out the original version by looking at commit history

Illustration showing a path with a starting point labelled “original”, with a note that this is called the “merge base”. Two paths, labelled v1 and v2, diverge from it.

panel 6: cherry-pick, revert, rebase, and merge all need to combine files

Illustration of a smiling stick figure with curly hair.

person: “they all use the same merge algorithm, using some clever tricks! we’ll talk about that next.”