Guides

Deeper reads on how the underlying formats and calculations actually work. Each guide links to the relevant tool so you can try it as you read.

6 min read
Reading a Mortgage Amortization Schedule
The monthly payment stays flat, but the money is going to very different places over time. Understanding the split is how you know whether extra payments are worth it.
Updated Aug 14, 2026
5 min read
How Base64 Encoding Actually Works
Base64 is not encryption, not compression, and not magic. It is a very specific mapping from 3 bytes to 4 characters — and that constraint explains almost everything strange about it.
Updated Aug 14, 2026
6 min read
JSON vs YAML: When to Use Which
Both encode the same shape of data, but they optimise for different readers. Here is how to choose.
Updated Aug 14, 2026