user11009: In Sutta pitaka we find two Suttas namely Jhana sutta and Samadhi sutta.
 What is the difference?
http://www.accesstoinsight.org/tipitaka/an/an04/an04.041.than.html
http://www.accesstoinsight.org/tipitaka/an/an09/an09.036.than.html

user10100: In tipitaka, buddha and sāvaka often use them as a synonym for each other.
Because when mind has just one focusing (jhayatiti jhāna) is when mind has concentration (samadahatiti samādhi).

user111: Samadhi is a general term for concentration. Jhanas are stages you achieve in Samatha meditation when your concentration reaches a certain level. 
To give an analogy, Samadhi is like the temperature of ice. When the temperature reaches a certain level, it becomes water. That's like reaching the first Jhana. If you keep heating, it will become steam. That is like reaching the second Jhana and so on.

11009: <p>In Sutta pitaka we find two Suttas namely Jhana sutta and Samadhi sutta.
 What is the difference?</p>

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 10100: <p>In tipitaka, buddha and sāvaka often use them as a synonym for each other.</p>

<p>Because when mind has just one focusing (jhayatiti jhāna) <strong>is</strong> when mind has concentration (samadahatiti samādhi).</p>
 111: <p>Samadhi is a general term for concentration. Jhanas are stages you achieve in Samatha meditation when your concentration reaches a certain level. </p>

<p>To give an analogy, Samadhi is like the temperature of ice. When the temperature reaches a certain level, it becomes water. That's like reaching the first Jhana. If you keep heating, it will become steam. That is like reaching the second Jhana and so on.</p>
