From an SEO point-of-view, which version is better:
<input type="text" name="q" value="search" />
or
<input type="text" name="query" value="search" />
Here's another example:
<input type="text" name="e" value="email" />
or
<input type="text" name="email" value="email" />
In other words: Does Google use the HTML input name attribute?
There is no SEO value in this. This is not content. Use form names that makes the server side programming cleaner and easier to manage. This is way over-thinking SEO.
When you use the HTTP GET method to submit the form, and the produced URL is allowed to be crawled/indexed, then it can matter for SEO in the way that it’s just another part of your URL.
<input type="text" name="e" /> might produce an URL like:
http://example.com/index?e=foo
<input type="text" name="email" /> might produce an URL like:
http://example.com/index?email=foo
If or to which extent such signals in the URL may matter for SEO is discussed in various questions here.
One thing is sure: If these URLs are indexed and a user is searching for "email", many search engines (including Google) will highlight occurences of this term in the search result snippet. This may lead to more clicks, even more so if the term in question is not also part of the page title/description.
