DevOps Classroom notes 05/Mar/2026

Lets continue commits and create a mental model (visual git)

• Lets create directory and make commits

mkdir commit_graphs
cd commit_graphs/
git init
touch Readme.md
git status
git add .
git commit -m "first"

• Now lets make some more changes

echo "hello" > Readme.md
git status
git add .
git commit -m "second"

• few more

echo "hello1" >> Readme.md
git status
git add .
git commit -m "third"

echo "hello2" >> Readme.md
git status
git add .
git commit -m "fourth"


echo "hello3" >> Readme.md
git status
git add .
git commit -m "fifth"

• Git always points to latest commit.
• What git is pointing is denoted by HEAD
• In git this graph starts with a default name called as master.
  
• Commit id is SHA1 Hash of
  • previous commit
  • current changes
  • author
  • datetime
  • message
• Git only tracks files not folders
• Using git add

git add <filename>
git add . # Add all changes in current and child directories
git add -A # Add all changes
git add -u # Add only modified changes

• Lets learn what is untracked and modified
  • untracked: is a new file which was not part of git commits
  • modified: existing file which was part of git commits changed
  • deleted: existing file which was part of git commits deleted
  • renamed (it will appear in staging area)