user86928: I was trying to interact with bitcoin network with JSON RPC commands, So I referred to the bitcoin wiki page https://en.bitcoin.it/wiki/API_reference_(JSON-RPC)#Java it shows to run the bitcoin using 'bitcoind -daemon' command. but another page of bitcoin wiki https://en.bitcoin.it/wiki/Running_Bitcoin suggest running the node using './bitcoind' command.so
 What is the difference between the two commands?

user59146: 
What is the difference between the two commands?

./bitcoind - runs bitcoin node in the foreground.
./bitcoind -daemon - runs bitcoin node as daemon.

What is daemon?

In multitasking computer operating systems, a daemon is a computer program that runs as a background process, rather than being under the direct control of an interactive user. 

86928: <p>I was trying to interact with bitcoin network with JSON RPC commands, So I referred to the bitcoin wiki page <a href="https://en.bitcoin.it/wiki/API_reference_(JSON-RPC)#Java" rel="nofollow noreferrer">https://en.bitcoin.it/wiki/API_reference_(JSON-RPC)#Java</a> it shows to run the bitcoin using 'bitcoind -daemon' command. but another page of bitcoin wiki <a href="https://en.bitcoin.it/wiki/Running_Bitcoin" rel="nofollow noreferrer">https://en.bitcoin.it/wiki/Running_Bitcoin</a> suggest running the node using './bitcoind' command.so
 What is the difference between the two commands?</p>
 59146: <blockquote>
  <p>What is the difference between the two commands?</p>
</blockquote>

<p><code>./bitcoind</code> - runs bitcoin node in the <strong>foreground</strong>.</p>

<p><code>./bitcoind -daemon</code> - runs bitcoin node as daemon.</p>

<blockquote>
  <p>What is <code>daemon</code>?</p>
</blockquote>

<p>In multitasking computer operating systems, a <code>daemon</code> is a computer program that runs as a <strong>background</strong> process, rather than being under the direct control of an interactive user. </p>
