This poignant observation is even more true for technical topics. It is essential for clear analysis of search results first, to know something precise about technical vocabulary, and second, to be absolutely rigorous when using these words in our thinking and communicating.
With this in mind I thought a thread about commonly misunderstood words and fuzzily understood technical concepts could be helpful.
1. Page Rank is not Ranking
Don't know why we can't put this craziness to bed, but it's still around. If anyone is not clear about this, read Google PR - PageRank FAQs [webmasterworld.com]
2. Site has no technical definition
Trust me on this one. There is a definition for "domain" but "site" is a casual word with no techical reality.
3. Page has no technical definition
Google indexes a url, not a page. For example, if the viewport of your computer displays an html document that contains an iframe, then there is content from two different urls being displayed.
4. alt is an attribute, and not a tag
You can look this one up. There is no such thing as an "alt tag"
5. title is either an attribute or an element
The attribute type of title does nothing to speak of for your rankings, right now at least -- although it can help your site's usability quite a bit. But the title element is probably the most important on-page factor there is for well-targeted ranking.
6. spidering and indexing are two different processes
Just because googlebot asks your server for a url does not mean that url is indexed. While we're at it, let's mention "caching" -- it's really a third process.
7. linked to and linked from are very different things
This seems obvious, and yet in technical discussions the fog of chaos often starts to build
8. rel="nofollow" is an attribute, quite different in effect from a robots meta tag nofollow
This one gets mangled a lot lately. rel="nofollow" just means "I don't vouch for this link - don't send PR, and please don't nail my domain if this happens to point to a bad neighborhood."