Question about Proxies importance

Hello,,,
I'm new with you, and I am an Arab,
After all I'm generally in the field of SEO
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I hear about social bookmarking sites
I know that when you publish any subject makes up ahead in the search results on Google

When I entered this forum for the first time I saw the appetite for this section Proxies

I want to know what is Proxy?
What is the benefit to the owners of sites?
What are how to use it?
I am have a site Can I use it at any thing would be useful?


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I apologize if there are errors in the language I use Google translator because I speak arabic only,

ohh.. so google translate is progressing very well.

btw, regarding proxies you can find everything from the link..(arabian version )
http://ar.wikipedia.org/wiki/Proxy_server

Refer to my this post will clear your concern

http://www.blackhatworld.com/blackhat-seo/proxies/605545-proxies-proxy-scraping.html#post6036145

What is a proxy: http://www.sslprivateproxy.com/what-is-a-proxy/
Why use a private proxy: http://www.sslprivateproxy.com/why-use-a-private-proxy/

Tutorials in how to use a proxies: http://www.sslprivateproxy.com/category/tutorials/