Reading What Everyone Already Did

Plain git log prints every commit in full, newest first, and opens a pager you then have to work out how to close. It is press q, by the way.

Nobody reads it that way. These are the shapes people actually use.

# One line each — the default view for most people$ git log --oneline # The last ten, with author and relative date$ git log -10 --pretty=format:"%h %ad %an  %s" --date=relative # Everything that touched one file, ever, including renames$ git log --follow -- src/auth/redirect.ts # Everything by one person, since a date$ git log --author="Sam" --since="2 weeks ago" # Commits whose message mentions a word$ git log --grep="redirect" # Commits whose DIFF added or removed a word — much rarer, much more powerful$ git log -S "loadUser"

That last one is worth pausing on. -S— the "pickaxe" — searches the content of the changes rather than the messages. It answers "when did this function first appear, and when did it get deleted", which is a question no amount of reading commit messages will answer reliably.

A linear log hides the shape of the history entirely. Adding --graph draws the branch structure in the margin with the same characters that make up every commit diagram you have ever seen.

$ git log --oneline --graph --all --decorate

*   9f3c1a2 (HEAD -> main, origin/main) Merge pull request #483 from fix/login|\| * 4b8e0d7 (fix/login) Handle the empty next param| * 2c7a91f Fix the redirect when next is empty* | 7d1f6b4 Add the settings page|/* 1a5e8c3 Set up the router* 0b2d7f9 Initial commit

This combination is common enough to be worth an alias. Git aliases are just config, and they work anywhere in any repository.

$ git config --global alias.lg "log --oneline --graph --all --decorate"# now: git lg

git diffwith no arguments is not "show me my changes". It is one specific comparison out of several, and picking the wrong one is why people conclude their changes vanished.

$ git diff                          # unstaged changes only$ git diff --staged                 # what you are about to commit$ git diff HEAD                     # everything since the last commit$ git diff main..fix/login          # what the branch changes$ git diff main...fix/login         # what the branch ADDS, ignoring what main did meanwhile$ git diff HEAD~3 HEAD -- src/      # three commits ago to now, one directory

The two-dot and three-dot forms are genuinely different and the difference matters on a branch that has been open for a while. Two dots compares the two endpoints directly, so it includes everything main did while you were away. Three dots compares against the point where the branches diverged, which is the change your branch is responsible for. GitHub shows the three-dot diff on a pull request, which is why the diff there is often smaller than the one you get locally.

Once git log has given you a hash, git show gives you everything about it: the message, the author, and the full diff.

$ git show 2c7a91f                  # a commit by hash — a short prefix is enough$ git show HEAD                     # the commit you are standing on$ git show HEAD~2                   # two commits back along the first parent$ git show main:src/auth/redirect.ts   # a whole FILE as it exists on main right now

That last form is quietly one of the most useful commands in Git. It prints a file from any commit or branch without changing anything in your working tree, so you can look at how something used to be while your current edit stays exactly where it is.

Hashes can be abbreviated to any unambiguous prefix — usually seven characters is plenty, and Git tells you if it is not.

git blame annotates every line of a file with the commit that last touched it. The name is unfortunate. The purpose is almost never to find somebody at fault; it is to find the commit message that explains a line you do not understand.

2c7a91f (Sam    2026-08-04 09:14:22 +0100 12) export async function loadUser(id) {2c7a91f (Sam    2026-08-04 09:14:22 +0100 13)   const res = await fetch(url);9a1c4e8 (Priya  2026-05-19 16:02:41 +0100 14)   if (!res.ok) return null;1a5e8c3 (Sam    2026-02-11 11:30:07 +0000 15)   return res.json();

Line 14 looks wrong to you. Blame says Priya wrote it in May, in commit 9a1c4e8. Now run git show 9a1c4e8 and read the message: it will very often say exactly why, and the reason will very often be one you had not thought of.