(1990) ˡ . 1997 10 2007 () ǡ () . (Keywords) ˡ
(backrub) 1998 (Google) (Page Rank) . (On Page) (Off Page). ɡ . . (1998 - 2005) (2007) ɡ (2009) "nofollow" "dofollow" . (2010) (50%) ( ) (Real time). (2011) (panda) . (2012) (Penguin) . (2013) (Hummingbird) . (2015) (Mobile-Friendly) .
(SEM). . ˡ
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( ) (: SERPs) (: CPC) ˡ .
. .
ɡ ɡ ˡ
SEO
ɡ on-page & Off-Page
: :
H1
: ˡ ɡ . . ʡ ( ). ߡ .
ɡ Google Yahoo Ask About Rank -- (Search Engine Optimizer) .