Chapter_1

1 - About Version Control

Version control systems save the history of changes to a file
- Doesn't have to be Source Code
Distributed Version Control systems like Git fully mirror the entire repo in clients

Git stores data as snapshots of a mini file system
- Most other (D)VCS's think of data as files with patches
Git operations are local unless explicitly targetting the server
Data is checksummed with SHA-1 and that checksum is used to determine if there are changes
As a general rule git is only additive, it rarely will remove data
Git files are in one of 3 states:
- Modified
  - Changed but not committed to the database
- Staged
  - Marked the current state of the file to go in to a commit
- Committed
  - All marked changes have been saved to the local database
Working Tree
- A single checkout of a version of the project
- Decompressed to your file system on request
Staging area
- Technical name is Index
- A file in the .git repo that contains info on what is going into the next commit
Git directory
- Contains metadata and the object database
- The only thing that is copied when doing a clone

Git can be configured with the git config tool or written to the config files
Config files are hierarchical, taking the "closest" relevent config
- /etc/gitconfig
- ~/.gitconfig
- .git/config
git config --list --show-origin
- View all settings and which file they were derived from
Important things to set
- user.name
- user.email
- core.editor

Useful commands from this chapter
- git config --global <config.option> <value>
- git help <verb>
- git <verb> --help
- man git-<verb>
- git <verb> -h
Working tree is a single instance of a version checked out locally
Staging area is called the index and is a file in the .git repo with info about the next commit
.git directory contains metadata and the object database
Three states are:
- Modified
- Staged
- Committed
Configure User name, email, and editor on a new install at minimum