Why do people type the URL in google and not in the browser's address bar?

- A question often asked (incredulously) by web teams looking at their data logs!

The answer is simple: it's usually quicker, requires less mental effort and is generally more fruitful to find the correct website address in a search engine than attempt to do so in the brower's address bar.

Let's see why that is:

1. Web addresses are difficult to type given the non-semantic elements and punctuation: http://www. my-site ...hyphen or underscore .com, .org or co.uk...?).
2. Web addresses can be hard to remember (was it british-airlines, ba, british_airlines, britishairlines...?).
3. They normally have to be 100% correct if you type them directly into the browser - although things are improving in this regard.
4. When you get the URL wrong, with a browser you get a dead end error page, though this is not the case with the search engines! Compare:
   

Search engines on the other hand forgive your spelling mistakes, make helpful suggestions and aren't picky about punctuation!

It comes down to basic usability principles - or common sense! In plain English, these are:

• Don't make me think
• Don't expect me to remember
• Forgive my mistakes, to err is human (and so am I)
  
• Be flexible with alternatives
• Give me an escape route

In conclusion, search engines are more generous than browers in all of these aspects, cause less frustration and make life easier. Just what good design is all about!
Perhaps the solution is to permanently replace the address bar with a search box...?