Link juice is the currency of Google. In other words, it's the secret sauce that allows you to beat your competitors for rankings in Google. Sure, there are some other factors that Google uses to calculate rankings (see Search Engine Optimization), but link juice is by far the most important aspect of dominating Google and in order to understand Google, you have to understand link juice.
Google looks at how sites link to each other to figure out which ones are the best. To show this in a way that's understandable, let's show a few examples. Let's say that Site A and Site B are both about 'some keyword' and would both like to rank for 'some keyword'.
Google is going to take a look at links to determine which of these two sites is likely the best. At the most basic level, let's say that Site A gets a link from a site that Site B doesn't get:
Site A now looks better to Google and will outrank Site B. Let's say that Site C decides to link to Site B, as well:
Now they both look the same to Google, who will now have to look at another ranking factor to determine which one is the best. There are other factors but none of them is nearly as important as the link juice factor.
Let's add two new sites into the mix to further illustrate different scenarios that can happen:
In the above example, we now have Site D linking to Site A and Site E linking to Site B. To figure out which site is better between Site A and Site B, Google will have to look at the sites that are linking to Site D and Site E:
In the above example, Site D has more link juice than Site E because it's getting links from Site F, Site G, and Site H. That means that Site A has more link juice than Site B. Site A will therefore outrank Site B.
Google is able to map out link relationships on an enormous scale and that's what makes them Google.
For competitive keywords, the ranking sites have millions of links from other sites who have hundreds of thousands of links from other sites who have links from other sites who have links from other sites.
There are also non-competitive keywords that would require very few links to get ranked #1 in Google. I have #1 rankings that were achieved because of one link. This happens because all of the other sites have zero links from other sites or they have links only from sites that have no juice.
Every keyword is different and if you want to rank #1 for your keyword, your job is to get more link juice than the other sites that currently show up for that keyword.
To increase your juice you need to get more links, especially from sites that have a lot of juice.
If you're trying to understand link Buy propecia online prescription juice, I'm guessing you want to improve your search engine rankings. Improving rankings is all about a) targeting the right keywords, and b) getting the right kinds of links.
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