What Is GitHub? A Guide for Engineers Who Don't Code
Almost every free engineering program on EngiFree eventually leads to a github.com address. This guide explains GitHub in engineering terms, shows how to download software from it without confusion, and how to use it to keep a history of your calculations, scripts and reports.
01Git vs GitHub: Track changes for a whole folder
You know "Track changes" in Word: you see who changed what and when, and you can go back. Git is the same idea for an entire folder of files, and it runs on your computer. GitHub is the website that stores those folders in the cloud, like Google Drive with a built-in time machine and a team message board. Git is the tool; GitHub is its home on the web.
02The basic words, in plain English
Repository (repo)
One project folder with its full history. For example, all the calculation files for one project.
README
The main explanation page of a repo, shown automatically. Like the cover sheet of a design file: what is here and how to use it.
Commit
A saved snapshot of the files with a short note, such as "Update wind loads per amendment 2". Every commit is a point you can return to.
Branch
A separate working copy where you try a change without touching the main version. Like working on design option B.
Pull request
A request to merge changes from a branch into the main version, with room for review and comments. Just like submitting a drawing to the checker before it joins the official set.
Release
A ready-to-download version with a date, notes and usually installer files. This is where you get the program itself.
03Words you will meet in open projects
Issue
A ticket for a bug or a request. Users report problems or ask for features, and the developers reply on the same page.
Fork
Your own copy of someone else's repo, which you can change without affecting the original.
Star
A like or a bookmark. Many stars suggest that many people know and use the project.
License
The file that says what you may do with the software: use it, change it, sell it. Without a license, the default is that copying is not allowed.
04How work flows on GitHub, in five steps
- 1RepoCreate a repository for the project and upload the files
- 2CommitEvery change is saved with a note: what you did and why
- 3BranchTry a big change on a separate branch without risking the main version
- 4Pull requestA colleague reviews the change, comments and approves the merge
- 5ReleaseMark an official version that others can download
05Why it matters to you: free engineering software lives there
FreeCAD
Parametric 3D modelling. The code and installers are published on the FreeCAD Releases page on GitHub.
OpenSees
Structural and earthquake analysis from Berkeley. The source code is managed in the OpenSees repo on GitHub.
QGIS
A free GIS system. Development happens on GitHub; the normal user download is from qgis.org.
CalculiX
A finite element program. It has a GitHub repo under its author's account, with official downloads at calculix.de.
KiCad
Electronic circuit design. Its main home is GitLab (a GitHub-like site), with a mirror copy on GitHub.
06How to download a program from GitHub safely
- 1
Start from the source
Reach the repo through the program's official website or the EngiFree link, not through an ad or a random link.
- 2
Find Releases
On the repo page, on the right side or near the top, there is a Releases link. A version marked Latest is usually the stable one; Pre-release means a test build.
- 3
Open Assets and pick a file
On Windows look for .exe or .msi, on a Mac a .dmg, and on Linux an .AppImage. Check the processor type (x86_64 or arm64).
- 4
Skip Source code
The Source code files (zip or tar.gz) are added automatically to every release. They are for people who build the program themselves, not for people who just want to install it.
- 5
Check signs of life
How many stars, when the last release came out, and whether there is a License file. A project not updated for years or without a clear license needs caution.
- 6
Scan before installing
Run the file through your antivirus, and if the project publishes a checksum, compare it.
07Example: version history for a calc sheet and scripts
08Example: reporting a bug in free software
09What to use for what: recommendations for common tasks
| What you want to do | What to use | Why |
|---|---|---|
| Download free engineering software | The project's Releases page | Official installers and release notes are there |
| Keep versions of calculations and reports | A private repo and GitHub Desktop | Full history without typing commands |
| Report a bug in a program | Issues in the program's repo | Developers see it and reply in one place |
| Work with a colleague on the same files | Branch and Pull request | Every change is reviewed before it reaches the main version |
| Let an AI agent improve a script | Claude Code, Codex or Copilot on the repo | The agent reads the files and proposes changes as a commit or Pull request you approve |
| A simple web page for a project or tool | GitHub Pages | A free static site from a public repo on the Free plan |
| Keep LaTeX or Markdown reports | A private repo | You see exactly which lines changed between versions |
10Get started in 5 minutes
- 1
Create an account
Sign up at github.com with an email and password, and turn on two-factor authentication.
- 2
Create a private repo
Click New repository, give it a name, choose Private and tick the option to add a README.
- 3
Upload files from the browser
On the repo page: Add file, then Upload files; drag your files in and write a note. Browser uploads are limited to 25 MiB per file.
- 4
Install GitHub Desktop
A free app for Windows and Mac that syncs a folder on your computer with the repo, with clicks instead of commands.
- 5
Make your first commit
Change a file, write a short note, click Commit and then Push. Now you have history.
11Common pitfalls: do and don't
Do
- Start with a Private repo for anything work-related
- Write clear commit notes: what and why
- Check the license before using software or code in a commercial project
- Download only from the Releases page of the official repo
- Turn on two-factor authentication
Don't
- Never upload passwords, API keys or client data, not even to a private repo
- Don't make a repo public without checking its entire history
- Don't assume deleting a file removes it from the history
- Don't download Source code when you only want to install
- Don't upload huge files: above 100 MiB you need a special tool (Git LFS)
12FAQ
Does GitHub cost money?
There is a Free plan with unlimited public and private repos, 2,000 GitHub Actions minutes per month and 500MB of Packages storage. Paid plans add team features. Check github.com/pricing for current details.
Do I need to know how to code?
No. To download software, report a bug or keep versions of files, the browser and GitHub Desktop are enough. Commands are useful but optional.
How do AI agents work with GitHub?
Agents such as Claude Code, Codex and Copilot can read a repo, edit files, commit, and open a Pull request that you review and approve. Capabilities and permissions depend on the tool and the plan. Copilot Free, for example, includes up to 2,000 code completions per month and limited chat and agent use. See also our guide to agents.
What is GitHub Pages?
A service that turns a repo into a free static website, for example an explanation page for a calculation tool you built. On the Free plan it works only from a public repo; paid plans also allow private repos.
Is a private repo really private?
Only people you invite can see it, but it is still a cloud service. Never keep secrets such as passwords and keys there, and store client data only if your contract and office policy allow it.
Do Excel and PDF files work well on GitHub?
You can store them and get history and roll-back, but GitHub will not show you which cells changed. Line-by-line comparison works for text files: CSV, Python, LaTeX and Markdown.