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Zoom classroom: https://sdccd-edu.zoom.us/j/9191959460?pwd=OXh0RE9ZTVZTWElTMUQ0ZzAxQzExdz09
Passcode: emeritus
QR codes are everywhere. They are small square images, usually black and white, which are crammed with data. They can be found in various locations like product packaging, advertisements, restaurant menus, websites, business cards, and even on clothing. Just looking at the QR code provides little help on its role, but using your phone or a special app you can find detailed information. In this class, we will look at the beginnings of QR codes, a key to unlocking the mystery behind those little mystery boxes, some applications of QR codes and potential risks to using random QR codes.
QR codes (Quick Response codes) are two-dimensional barcodes that can be scanned by digital devices to quickly access information. Unlike traditional one-dimensional barcodes that can only store information horizontally, QR codes store data both horizontally and vertically, allowing them to hold significantly more information in a smaller space.
Seven minute video on QR codes
QR codes were invented in 1994 by Denso Wave, a subsidiary of Toyota, in Japan. They were initially created to track automotive parts during manufacturing, but their utility quickly expanded beyond the automotive industry. The QR code technology was released with an open license, which helped accelerate its adoption worldwide.
QR codes can be found on many applications including:
Retail and marketing: Linking to product information, promotions, or online stores
Contactless payments: Mobile payment systems like Apple Pay, Google Pay
Ticketing: Event tickets, public transportation
Business cards: Quickly sharing contact information
Restaurant menus: Accessing digital menus
Inventory management: Tracking products through supply chains
Authentication and security: Verifying identity or product authenticity
Healthcare: Patient identification, medication information
Tourism: Providing information about landmarks or exhibits
These versatile codes have become increasingly prevalent in our daily lives, especially surrounding Pandemic when we were avoiding contact. They offer a bridge between physical objects and digital information.
A QR code consists of black squares arranged on a white background. The key components include:
Position detection patterns (the three large squares in the corners)
Alignment patterns (smaller squares)
Timing patterns (alternating black and white modules)
Version information
Format information
Data and error correction codewords
QR codes employ error correction capability using Reed-Solomon codes, which allows them to be readable even when partially damaged or obscured.
Want to better understand QR codes? This video explains how they started and how they are created. (6:30)
Below are four examples of QR codes. Look at them and see if you can identify some of the components from the above example. Do not scan them yet, just look at them! How many of the features above can you find in these QR codes?
What about those other types of codes? This video walks you through them, and suggests an app which can read all of the different QR codes (available in Apple and Google Play)
In order to scan the QR code, you need a smartphone (Android or iPhone), your built-in camera app and an Internet connection.
For iPhone Users:
Open your Camera app - Tap the Camera icon on your home screen
Point your camera at the QR code - Hold your phone so the QR code appears in the viewfinder
Wait for detection - Your phone will automatically detect the QR code; you don't need to take a photo
Tap the notification – Although most commonly it is found at the top of the screen, there are other locations where the QR code scan notifications may occur. The notification is designed to be visually obvious. Other places where you might find a QR code include just below the QR code, at the bottom of the screen, in the center of the screen or as a small icon in the view finder.
View the content - The website, menu, or information will open automatically
For Android Users:
Open your Camera app - Tap the Camera icon on your home screen
Check settings if needed - Some Android phones require enabling QR scanning in camera settings first
Point your camera at the QR code - Position your phone so the QR code is clearly visible
Tap to scan if needed - Some Android phones require tapping on the QR code in the viewfinder
Tap the notification - When a notification appears, tap it to open the link. Remember that the notification may end up just below the QR code, at the bottom of the screen, in the center of the screen or as a small icon in the view finder. But the notification is designed to be visually obvious.
View the content - The website or information connected to the QR code will open
Scanning a QR code without using your camera app
If you do not have the capability to use your smartphone, there are other options:
Dedicated QR code scanner apps: Download these from your app store. Some of these, such as QR Scanner for Micro Trend, may have added security features that check URLs before opening them.
Social media apps: Some of them allow QR scanning capacities. For example, in Snapchat, you can use the camera and hold it over a QR code while pressing on the screen.
Screenshot method (explained below). Once you have the screenshot, you can view on a web-based QR reader like webqr.com. This is also nice because you can clearly see the information before you click on anything.
Troubleshooting Tips
Make sure your camera lens is clean
Ensure there's enough light to see the QR code clearly
Hold your phone steady while scanning
If scanning doesn't work, check your camera settings to ensure QR code scanning is enabled
Safety Note
Always check the URL that appears before tapping to open it
Be cautious about scanning QR codes from unknown sources
Activity: Let's go back to the examples above and scan them!
Maybe you are using a link to a QR code that someone has sent you. Of course, before doing this, review the safety tips below. (QR codes can be created by anyone, and you don’t know where the link is taking us.)
You first need to take a screenshot of the QR code. Depending on your device, this may be one of two methods:
• Press the Home and Power button at the same time
• Press the Power and Volume Up button at the same time
After taking the screenshot, you will save it in your photos folder, then open it to find the destination. The directions are a little different for iPhone and Android:
Steps while using iPhone::
Take a screenshot (side button and volume up)
Save in your photo’s app
Open photo in your photos app.
Tap and hold down until you see “Open in…” depending on your default browser
You will be sent to the destination of the QR code
With Android, the instructions are similar, but you will be using Google photos
Take a screenshot (side button and volume up)
Save in Google Photos
You can open that in the notification window. If you miss this, go to Google photos and tap on the image.
Select “lens” from the bottom of the screen
Choose one of the options (website, copy URL, share, etc.)
For our class, find one method that will work for you (smartphone app, smartphone camera).
Depending on what you want the QR code to point to, there are different methods to help. In general, you would use a browser to create a QR code to an URL, and a third party app to create other QR codes (like Wi-Fi, name card, link to YouTube, etc.)
Method: From a browser:
Chrome:
Find the webpage that you want to create a QR code for.
Click on the 3 dots in the upper right of the screen
Scroll to Save and Share
Select “Create QR code”
Copy the code and paste it into a document of where you would like to save it.
Or, you can download it, save it and share.
Brave: Directly from address bar
Click on the box with the arrow (address bar)
Select “create QR code”
Edge: Download extension from Microsoft store
Click on the extension icon in the top bar
Select Get Extensions for Microsoft Edge
Search for “qr code generator”
Choose one (look at reviews and number of reviewers)
Then, when on a web page you want, click on the extension icon and select “qr code generator”
Safari:
You cannot create a QR code in Safari, but you can create one using a third-party QR code generator like QRCode Monkey (instructions below)
Create with 3rd party app:
If you want to create a QR code for different things (contact information, directions, invitation, Wi-Fi password) or if your browser is not creating QR codes for you, you can create a QR code using a 3rd party website like QR Code Monkey (https://www.qrcode-monkey.com/)
1. Go to site
2. Select type of QR code (such as URL, contact information, a link to a website)
3. Enter the URL or other data you want the QR code to contain
4. Click “Generate QR code”
5. Customize as needed
6. Click download to save to your device
While they were very popular during the time of Pandemic for saving menus, there have become problems with illicit QR codes. When using them, you need to be sure that they are legitimate. Note that there are videos below which highlight how hackers can change them and a public news story on fake QR codes.
How to identify potentially unsafe QR codes:
Unfortunately, there's no foolproof way to visually determine if a QR code is malicious just by looking at it, but here are some safety practices:
Physical Inspection
Look for tampering - If a QR code looks like it has a sticker placed over the original, it might be compromised
Check for official placement - QR codes in unexpected places (like randomly stuck on walls) are more suspicious than those on official materials
Quality and presentation - Legitimate businesses typically display QR codes professionally with clear instructions
Before Tapping the Notification
Preview the URL - Check if the web address matches what you expect (e.g., a restaurant's actual website)
Watch for misspellings - Fraudulent URLs often use similar but slightly misspelled domain names
Be wary of shortened URLs - These hide the actual destination (like bit.ly or tinyurl links)
Check for secure connections - Look for "https://" rather than "http://" in the URL
General Safety Practices
Don't scan codes from untrusted sources - Be especially cautious with codes in public places or unsolicited emails
Use QR scanning apps with security features - Some dedicated QR scanner apps check URLs against known malicious sites
Never enter personal information or passwords after scanning unless you're certain the site is legitimate
Trust your instincts - If something seems off about where the QR code is taking you, close the page immediately
For more information on how QR codes can be used for harm, review this website.
Video: He talks a little fast, but does show us how QR codes can be hacked.
Video: Learn more about how scammers can use QR codes to scam.