here is most common issue in SEO Practices, search engine
and website owners that is Canonicalization.
Canonical Tag is the best option for dealing with duplicate
content pages. Canonical Tag passes the
same amount of link juice ( PR, PA,DA) to the destination url.
Syntax for canonical tag is <link
rel="canonical" href="your destination url" >.
One thing kept in mind that canonical tag put in head
section of the web page.
Canonical is used for following instances:
 |
| Canonical Tag |
1. When dynamic URL generated with every new visit.
its depend upon how a user or visitor goes through your
website. these type of instances generally occurs in E Commerce websites.
example of this instance -
Suppose a user come on abc.com and click on product category1 and then after
product sub category
Finally he would be reached product zzz.
url --
http://abc.com?prodcat1?prodcat2=zzz.
in other situation if a user directly comes on zzz product .
Then url would be -- http://abc.com?info=zzz
in both example user reached on same product with different
url.
in these type of situations we are unable to use 3
01 redirect so we will use canonical tag .
2. Syndicated content- Google announced in 2009 that Cross
domain use of canonical tag.
it means if a publisher published its content on different
website then use rel tag for this. Reason behind it is that only one version of
content is eligible for ranking in SERP.
3. Multiple version of same page
http://example.com
http://example.com/index.php
http://example.com
Above three url's are same for user but crawler consider
them three different pages with same content.
So we can use redirect over here like < link
rel="canonical" href="http://www.example.com">
Why Canonical tag used instant of 301 server redirect ?
Their is only one reason behind it that is - Canonical Tag
pass 99 % Link juice to canonical url but 301 redirect pass approx 90-99 % Link
Juice. According to Google use 301 redirect whenever canonical tag is not
possible
301 Redirects –
 |
| 301 Redirect |
A 301 redirect is a server side redirect designed for moved
from old url to a new URL permanently. 301 redirect passes the link juice
between 90-99% to the redirected page, and according to Google, are the best
way to move url permanently.
When we will use 301 redirects
1. Moving a website to a New Domain
if you want to move your website to new domain or changaing
the structure of URL's then you should be use 301 redirect.
2. Multiple Ways to reach
Homepage
if your website have multiple ways to reached home Page .
(common issue with and without www ). for this issue you should use 301
redirect.
example :
http://doesseo.blogspot.com
http://www.doesseo.blogspot.com
in this situation
pick one of these URLs as your preferred destination and use a 301 redirect
.
Generally www.doesseo.blogspot.com would be used as preferred domain .
3. If your website have old products and content , and you
will want to move this old product to new one . then you would be used 301
redirect to relevant pages.
4. When your website or blog have some 404 pages then you
would be permanently moved these url to home page or their relevant pages.
