Git Basic – easy start

This blog entry gives a quick insight into the Git basics, is aimed at beginners and should make it easier to work and get started. The very first steps are shown, the most important functions are presented, as well as the advantages and disadvantages are considered and a comparison to SVN is made. For advanced users, further entries will follow, which take up various focal points, advanced functions and graphical GUI clients.

What is Git?

Git is a distributed versioning system for managing files. Typical for Git are a non-linear development and a decentralized storage. There is a central repository, but each user has a local copy including the corresponding versions, which also represent a backup (distributed system). A continuous connection to the remote repository is therefore not mandatory, only for synchronization. In addition, Git is platform-independent and can therefore be set up in almost any environment.

First steps and main functions

Git comes “out of the box” with a command line, without a GUI. For some this is a great thing, others prefer to work with one of the many graphical interfaces or use plug-ins that are available for various editors. One advantage of the command line in contrast to all the GUI alternatives is that really all available Git commands can be executed. The first and most important steps after installation are as follows:

The (basic) configuration

git config -1	View configuration
Git config –global user.name „Max Mustermann“	Set up user (will be displayed in every commit)
git config –global user.email „max.mustermann@in-factory.com“	Set up email
git config user.name	Query individual configuration
git config –global init.defaultBranch main	Configure branch name “main”

Create/clone the repository

git init	initialize a new repository (for this you have to be in the respective directory)
git status	Get status in the repository
git clone /verzeichnis/repository	creates a local copy of a repository
git clone benutzername@host:/verzeichnis/repository	creates a local copy of a remote repository

The Workflow

“Git defines three main states that a file can be in: committed, modified, and marked for commit.

Modified means that a file has been modified but not yet checked into the local database.

Staged means that a changed file is marked in its current state for the next commit.

Committed means that the data is stored securely in the local database.“ (vgl. Scott Chacon & Ben Straub, Pro Git (Second Edition)¹, 2021, S. 17)

Add & Commit

git add	Add file (staging)
git add *	add all files in the directory (staging)
git commit	Commit “saves” the new version (affects the local repository, not the remote one)
git commit -m „Message Text“	Commit “saves” the new version with comment
git log	List commits
git reset	Undo action

“Upload” the changes

git push origin	Sending changes in the local repository to the remote repository
git remote add origin	Upload the created repository

Branching

Branches, an essential difference to SVN, are used to isolate different developments from each other. The master or main branch is the main branch of each repository. During development, other branches should be used, which are then merged with the master or main branch at a later stage.

git checkout –b	create new Branch
git checkout master	Change branch to master branch
git branch –d	Delete branch
git push origin	Upload branch to remote repository (make it available for others)

Update & Merge

git pull	pull latest state from remote repository to local repository
git merge	merge a branch with the current repository
git diff	Show differences between two branches

Tagging

git tag 1.0.0	create a new tag (release tags as known e.g. from SVN, the Commit_Id is referenced with the tag)
git log	View commit list

Undo changes

git checkout —	Reset locally changed state to the checked-in state
Git fetch origin Git reset –hard origin/master	Discard local version and get state from remote repository
git revert	Reverse commit

Lifecycle status of a file in Git

Advantages

• Parallel working (decentralized, branching)
• Security through distributed repository
• Flexibility through different working methods
• Offline work possible due to decentralized and linkable structure
• Extensibility (various web clients and plug-ins)
• for free

Disadvantages and critics

A big point of criticism is the not so easy learnability. For beginners, the terminology is partly new and users of other systems are sometimes irritated, e.g. “-revert” means something different in SVN than in Git.

For example, if you want to completely record the structures of empty directories for a reason, Git is not suitable. If the directories have no content, Git discards them.

Comparison with SVN

Whether Git or SVN, they are probably the two best known among their kind and both have their respective advantages and disadvantages. Here are the most relevant differences:

	Git	SVN
Version control	distributed	central
Repository	local repository copies, in which development takes place	central repository where work progress is created
Connection with network	Only required for synchronization	for each access
Permission/Access	complete directory	path-based
Changes	Records content	Records files
Traceability/History	Repository and local copies contain complete history	only complete in the repository, local copies contain only the latest version

¹The book is free to download here