Out of sight is out of mind — they’ll never know!

Woman gesturing us to be quiet
Woman gesturing us to be quiet
Photo by Kristina Flour on Unsplash.

Steganography is the practice of concealing messages or information within other non-secret text or data. Using the following Python code, you can hide text messages within image files, and the human eye will not be able to see any change in the file’s image. They won’t know what they don’t know.

Just a Tiny Bit of Change

So, how in the world is it possible to hide hundreds of lines of text in a picture without anyone detecting the change? If you check the properties of an image file, you’ll discover that it has a width and height expressed in terms of pixels — the tiniest…


Be prepared to surprise them during your next job interview!

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Photo by Mohammad Rezaie on Unsplash

As the story goes, a bright young programmer interviewing at Google (or was it Microsoft? Or Facebook? … take your pick) was asked to explain why manhole covers are always round, and not square or some other shape.

The standard, very logical explanation is that round covers won’t fall through the hole they cover, taking into account the lips around the edges of the lid and the hole it snuggly fits into. Supposedly, round is the only shape where this is possible.


Take charge of your money management challenges the easy way

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Photo by Sharon McCutcheon on Unsplash

Bean counting is boring. At least that was the assumption I lived with most of my life. But the following short Python programs are easy to set up and run (they’re free too!) and they can help you take control of your personal financial decisions. Once again, Python has helped me hack my life in good ways, and it probably can help you too.

1. Payments for That New Car

Taking out a loan can be intimidating. A huge step towards making the process more comfortable is to have a good idea ahead of time what your monthly loan payments will be. …


Thinking outside the box just might help save us all

My wife wrote a screen play, “Lagrange Lancelot”, where the planet is saved from climate disaster by a unique geoengineering idea. It’s a very cool storyline, resulting in world peace as a by product after drastically slowing down a climate disaster. I just wish the fate of our planet, in the very real world, was also that cool.

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Photo by Melissa Bradley on Unsplash

Houston, We Have a Problem

We are in dire straights. My goal here is not to dwell on all the scary news. You can Google on “climate change” to find all the latest on that, from the…


You don’t have to rely on what ANYONE tells you!

There’s a ton of anecdotal descriptions and opinions out there explaining why the Earth must be flat, or why it can’t be flat. But why latch on to someone else’s opinion or facts one way or the other, even if their explanations and arguments seem very logical or perhaps based in science?

If you trust science and the scientific method to provide accurate results and facts, like I do, then you’re all set. The Earth is round. …


Our Moon is an odd ball. Very odd.

Pink Floyd had it right — there really is a dark side of the Moon. Let me explain.

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Photo by Neven Krcmarek on Unsplash

Obviously Odd Features

Consider that the Moon always keeps the same side facing the Earth — we never see its back side from here. Scientists explain this as a feature of “tidal locking”, where the internal stresses from slight bulging due to the forces of gravity have slowed the Moon’s spin to a relative standstill. …


Don’t waste time learning yet another proprietary 3D design language.

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3D printing your own creations is awesome! Perhaps Santa brought you one of the new, lower priced 3D printers for Christmas, or maybe you recently discovered that many public libraries and “makers” clubs make it easy (and cheap) to turn your ideas into real, tangible, 3D creations. In any case, this new hobby, entrepreneurial, or arts-and-crafts creation craze is catching on fast. OpenSCAD makes the design process simple, and Python makes using OpenSCAD even better.


Here’s a simple, short, secure Python script that lets you take control.

Keep the bad guys out of your stuff!
Keep the bad guys out of your stuff!
Photo by Bermix Studio on Unsplash

Passwords are a pain in the butt. There’s no way around this fact. In today’s world there are way too many passwords to remember, which leaves most people with one of three options; either start repeating passwords, or parts of passwords, write them all down somewhere for supposedly easy reference, or install a free or commercial password manager program.

Limitations of a password manager program

A password manager program is a good choice, but there’s a learning curve, you still need to memorize at least one really strong password to get into your passwords…


You can try this at home, but do it the easy way

You have to throw a lot of darts to estimate pi
You have to throw a lot of darts to estimate pi
Courtesy of icon0.com on Pexels

Imagine a special, square dartboard, say exactly 2 meters by 2 meters in size, with a giant bullseye circle inscribed within its borders.


Pictures of Uranus are tricky, but yes, it’s very true

My goal is to photograph the trails of satellites in the night sky, with known stars in the background, to enable analysis with Python scripts to calculate things like altitude, velocity, and other parameters. My passion is using Python for creative and fun real-world applications, and this night-sky application seemed like a good challenge.

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Photo by Usukhbayar Gankhuyag on Unsplash

Updated Camera

About a week ago I traded up my phone for a Samsung Galaxy S20 Ultra model. I chose this phone for its cameras, although there are several other phones available with similar capabilities suitable for various…

John Clark Craig

Author, inventor, entrepreneur — passionate about alternate energy, technology, and how Python programming can help you hack your life.

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