Here's why:
* "Web log" is a compound noun, meaning it's made up of two words that work together to describe a single thing.
* Compound nouns are typically written as one word (like "website") or with a hyphen (like "web-based").
* "Blog" is a shortened form of "weblog" and is now the most commonly used term.
Capitalization Rules
You should only capitalize "web log" if it's:
* The official name of a specific blog: For example, "The Daily Web Log"
* Part of a title: For example, "My Web Log About Travel"
Let me know if you have any other capitalization questions!