Topic 1: The Linux Community and a Career in Open Source

Linux

An open-source operating system inspired by Unix. One of the most popular operating systems available today.

Linus Torvalds

A finnish graduate student who developed Linux starting in 1991 and subsequently distributed it under the GNU Public License.

Unix

Operating system developed by AT&T in the 1970s. It is considered portable, meaning it can run on just about any hardware platform.

Linux Distribution

Bundles of software, such as Ubuntu and Mint, that contain the Linux kernel, utilities and a graphical desktop; also called distros.

Debian

A distribution family that uses the package manager dpkg and the package format deb

dpkg

Package manager used by Debian GNU/Linux, Ubuntu, and other Debian derivatives

deb

Package format used by the dpkg package manager

Debian GNU/Linux

The biggest Debian distribution; launched by Ian Murdock in 1993

Goal: Very reliable OS

default of no proprietary software

Ubuntu

A Debian-based distribution created by Mark Shuttleworth in 2004.

Mission to provide cheap+easy access to Linux desktop environment

release every 6 months, long-term support release every 2 years

Red Hat

A Linux distribution family that uses Red Hat Package Manager (RPM). The developer formed a company by the same name which specializes in open source software.

rpm

Red Hat Package Manager

RHEL

Red Hat Enterprise Linux: a distribution developed+maintained by Red Hat company (aquired by IBM in 2019)

Started in 1994, rebranded RHEL in 2004

Reliable enterprise solution, has subscriptions and/or licenses and fees

Commercial support

Optimized for servers

CentOS

a project that compiles RHEL into a free distribution (that doesn't have commercial support)

optimized for servers

Fedora

A Linux distribution developed by the community-supported Fedora Project and sponsored by Red Hat. Fedora contains software distributed under various free and open-source licenses and aims to be on the leading edge of such technologies. Free.

SUSE

A distribution of Linux most known for its YaST configuration tool

Embedded Systems

Computer system hidden inside another device, such as a car engine management system. A common place for embedded software--linux being the most common OS for embedded software

Android

A mobile OS developed by Google. Uses a modified Linux kernel and additional OS software. Almost always shipped with proprietary Google software.

Raspberry Pi

A low cost credit-card size computer that can function as a desktop computer or in an embedded Linux system. Developed by an educational foundation in the UK. Meant to teach young people how to program; also used in DIY or prototyping

Raspbian

A Debian-based computer operating system optimized for Raspberry Pi.

IaaS

Infrastructure as a Service. Often offers images of Linux distributions. User selects an image and accesses a cloud instance running the selected distribution

Package Manager

A tool that helps users install, manage, and remove packages or applications

Debian distribution (dpkg, apt-get, apt)

Red Hat distributions (rpm, yum, dnf)

sudo

run a command as sysadmin/root

apt

commands used for managing DEB packages. See also: apt-cache, apt-get

yum

command interface used for RPM packages. See also: dnf

dnf

Updated version of yum command and used to install and remove software on Red Hat

Apache OpenOffice

open source office suite managed by the Apache Foundation

LibreOffice

An open source office suite forked from Open Office. It includes tools that strive for compatibility with Microsoft Office in both features and file formats. More popular than OpenOffice

Blender

A 3D renderer used to create animations and export 3D objects

GIMP

full-featured image editor (similar to photoshop)

Inkscape

Vector graphics editor

Audacity

An audio editor

ImageMagick

A command line tool to convert and edit most image file types. It can also be used to create PDF documents from image files and vice versa.

VLC, smplayer

applications for video playback

HTTP server

Is the server part of the request and response cycle. In a local development environment, you must create an instance of an HTTP server to be able to communicate with the Client (browser) so that you can preview your work. Complex IDE's handle the instantiation of HTTP Servers for you. However, when using more simplistic source code editors, you must create an instance of one yourself.

Apache

An open-source web server software, widely used for hosting websites

Nginx

An open source web server based out of Russia focused on the use of more modern UNIX kernels.

lighttpd

A web server

MySQL

The most common version of the Structured Query Language

MariaDB

An open source database application forked from MySQL. It records data written to it by dynamic web applications.

PostgreSQL

A common SQL server used on Linux computers.

NFS (Network File System)

Is a client/server application that lets a computer user view and optionally store and update file on a remote computer as though they were on the user's own computer. The user's system needs to have an NFS client and the other computer needs the NFS server.

Samba

a data sharing protocol for multiple OS

ownCloud and Nextcloud

cloud computing data sharing

DHCP (Dynamic Host Configuration Protocol)

A service used to dynamically assign TCP/IP configuration information to clients. DHCP is often used to assign IP addresses, subnet masks, default gateways, DNS server addresses, and much more.

DNS (Domain Name System)

The Internet's system for converting alphabetic names into numeric IP addresses.

source code

A program in a high-level language before being compiled.

compiled languages

A compiler program translates source code (what the programmer writes) to machine language (object code)

A linker program puts various object code files together into an executable program (or other target type, like a DLL)

C and C++ are compiled languages

interpreted languages

source code is directly run on an interpreter, a program that runs the code statements

Perl

A programming language used to process text content with a focus on regular expressions

Shell

Includes the Bash shell. Is more than a programming language. An interactive interface to run programs. Shell scripts automate complex or repetitive tasks on the command line.

LAMP server

combination of Linux OS, Apche, MySQL DMS, and PHP

free software

Software that is free to run, copy, change or adapt, and share with friends, family or colleagues.

free as in 'free speech' not 'free pizza'

The four essential freedoms of software

Freedom to run the program as you wish, for any purpose. Freedom to study how the program works, and change it so it does your computing as you wish. Freedom to redistribute copies so you can help others. Freedom to distribute copies of your modified versions to others (with the same freedoms)

proprietary software

Software that has been developed by a company and has restrictions on its use, copying, and modification.

FOSS

Free and Open Source Software

FLOSS

Free/Libre and Open Source Software

GNU Not Unix

Recursive acronym which describes the free software project--copyleft, social and political movement. In contrast, Open source is more pragmatic-technical with more permissive licenses.

Open source vs free licenses

'free' licenses are copyleft, restrictive, and follow all four freedoms. Open source licenses refer to licenses which are less restrictive (usually without the 'must redistribute under the same license' restriction)

Free Software Foundation (FSF)

An organization, started by Richard Stallman, that promotes and encourages the collaboration of software developers worldwide to allow the free sharing of source code and software programs.

Has the GPL and others, as well as recommendations on other licenses

GPL

GNU General Public License which guarantees the freedoms to use, study, share (copy), and modify the software

LGPL

The GNU Lesser General Public License is often used for open source libraries.

If you simply compile or link an LGPL-licensed library with your own code, you can release your application under any license you want, even a proprietary license.

But if you modify the library or copy parts of it into your code, you'll have to release your application under similar terms as the LGPL.

AGPL

GNU Affero General Public License.

Covers selling access to hosted software

FDL (GNU Free Documentation License)

Extends freedoms to software documentation

copyleft

A licensing protection used by those who create open source software wherein the same license must be used in derivations

OSI

Open Source Initiative. Mostly concerned with licensing issues. Approves many licenses the GNU/FSF rejects. Not necessarily copyleft

Permissive License

An open-source (as opposed to copyleft/'free') license

BSD

Berkeley Software Distribution, a UNIX variant that gave rise to BSD license

FreeBSD License

aka 2-clause BSD License or simplified BSD license

Short and sweet

Creative Commons

A global nonprofit and license. Same principle as Open Source, applied to creative items. Has a list of considerations that varies by license--needs attribution, share-alike, no derivatives, etc

crowdfunding

raising money for a project or venture by obtaining many small amounts of money from many people, often in return for bonuses or benefits

dual licensing

free software is offered in parallel to restricted or proprietary software, which is a better version (think free vs paid versions)

professional services

The program is offered open-source or free, but technical support is available with a fee

by commission/funding

developing customer-specific extensions by order (I'll pay you to add support for X). Can be released under license or not. More common with smaller projects

Software as a Service

A cloud provider runs Customer Relationship Management (CRM) or Content Management System (CMS) to provide customers access to an installed application

CRM Software

Customer Relationship Management (SaaS)

CMS software

Content Management System (SaaS)

GUI

Graphical User Interface. Any interface that is more than the terminal/command line likely counts as this.

Command Line

a location on your computer screen at which you type text entries to communicate with the computer's operating system

Gnome

Linux desktop environment; follows KISS (Keep it simple stupid) principle. Streamlined and clean. Uses GTK toolkit, C language

KDE

Linux desktop environment. Uses Qt (C++). Larger application selection, and greater customizability

Impress

LibreOffice powerpoint

Open Document Format

International standard for a kind of file

Beamer

LaTeX class that creates presentations from LaTeX code

Reveal.js

NPM package that creates beautiful presentations using the web (you need to know html/css)

GanttProject

_______ is a free open source program that has a similar look and feel as Microsoft Project.

ProjectLibre

Linux Microsoft Project alternative

hypervisor

Software that creates and manages virtual machines on a server or on a local computer. Also called virtual machine manager (VMM).

Xen

Linux opensource hypervisor. Oldest of the three

KVM

Linux opensource hypervisor. Sponsored by RedHat

VirtualBox

Linux opensource hypervisor. Belongs to Oracle

KeePass

Open source password manager (file)

Bitwarden

Open source password manager (cloud)

TLS

Transport Layer security. A protocol that offers security over network connections using cryptography. Used on HTTPS

GnuPG

GNU privacy guard. It's an open source implementation of OpenPGP. Can sign, encrypt, decrypt, various things. Notably email.

stacked encryption

files are encrypted before being stored and decrypted after reading them

block encryption

'under' the filesystem layer. Everything that's written to the device is encrypted, including filesystem type and structure

dm-crypt

de-facto standard for block encryption on Linux

LUKS

Linux Unified Key Setup. Extension of dm-crypt

EncFS

stackable encryption. Easiest encryption on Linux

Veracrypt

multi-platform encryption program