Blog
Longer explainers on the ideas behind the tools: how averages mislead, why leap years exist, what makes a password strong, and more.
Start here
- Article · September 19, 2026How to Create a Strong Password (Length Beats Complexity)Strength comes from randomness and length. Here is how to measure it, and why unique passwords and a manager matter most.
- Article · September 19, 2026Percent vs Percentage Points: What Is the Difference?One is a subtraction of two percentages, the other a comparison with the starting value. Mixing them up misleads readers.
Percentages
Percentages, percentage change, discounts and how to avoid the usual mistakes.
Dates and time
Working out ages, date gaps, hours worked and how the calendar really behaves.
- Article · September 19, 2026Decimal Hours Explained: Why 7:45 Is Not 7.45Minutes are out of 60, decimals are out of 100. Converting between them is a simple division once you see why.
- Article · September 19, 2026Why Leap Years Exist and How the Rule WorksEarth takes about 365.2422 days to orbit the Sun. The leap year rule is a way of keeping the calendar in step with the seasons.
Money basics
Interest, loans, tips, salary and savings explained with worked examples.
Math and statistics
Averages, ratios, fractions and the statistics ideas behind them, with worked examples you can check by hand.
Conversions
Units, systems of measurement and how to convert between them correctly, with exact conversion factors.
- Article · September 19, 2026Kilobytes vs Kibibytes: Why a 1 TB Drive Shows LessStorage makers count in thousands, while some software counts in 1,024s. Both are right, and the units have different names.
- Article · September 19, 2026Metric vs Imperial vs US Customary: Why There Are Two SystemsMost of the world uses metric, but miles, pounds and gallons persist. The two families are now tied together by exact definitions.
Privacy and security
How password strength works and the everyday habits that keep your online accounts safe, explained without jargon.