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    <p><code>||</code> and <code>&amp;&amp;</code> uses <a href="http://en.wikipedia.org/wiki/Short-circuit_evaluation" rel="nofollow noreferrer">short circuit evaluation</a></p> <p>From <a href="http://en.wikipedia.org/wiki/Short-circuit_evaluation" rel="nofollow noreferrer">same article</a></p> <blockquote> <p>Short-circuit evaluation, minimal evaluation, or McCarthy evaluation denotes the semantics of some Boolean operators in some programming languages in which <strong>the second argument is only executed or evaluated if the first argument does not suffice</strong> to determine the value of the expression</p> </blockquote> <p>Consider you have an object and you want to check one of its property for some value if you do:</p> <pre><code>if(obj != null &amp; obj.ID == 1) </code></pre> <p>If your object <code>obj</code> is null you will get a null reference exception, since you used single <code>&amp;</code>, the first condition evaluate to <code>false</code>, but it will still continue to the next condition and raising null reference exception. </p> <p>If you used <code>&amp;&amp;</code> then the second condition will never get evaluated, thus no exception. </p> <pre><code>if(obj != null &amp;&amp; obj.ID == 1) </code></pre> <p>With your code you will not see any difference, but using bitwise <code>|</code> or <code>&amp;</code> with multiple conditions would result in no short circuiting at all. </p> <p>More Explanation. </p> <hr> <p>consider that you following code:</p> <pre><code>Boolean conditionA = 2 &gt; 1; //some condition which returns true if(conditionA | obj.SomeTimeConsumingMethod()){ } </code></pre> <p>Now in above code snippet, suppose you have an object with a method <code>SomeTimeConsumingMethod</code> which takes a lot of time in processing and returns <code>true</code> or <code>false</code>. If you use single <code>|</code> it would evaluate both the conditions, since first <code>conditionA</code> is <code>true</code> it will process <code>obj.SomeTimeConsumingMethod</code> as well. End result will be <code>true</code> for the whole <code>if</code> statement since <code>|</code> <em>(OR)</em> is used. </p> <p>If your condition is using double <code>||</code> <em>(OR Logical operator)</em> </p> <pre><code>if(conditionA || obj.SomeTimeConsumingMethod()) </code></pre> <p>Then the second condition <code>obj.SomeTimeConsumingMethod()</code> will not be evaluated. This is short circuiting and that just saved you from executing some time consuming method. Still the end result is <code>true</code> regardless of what was returned from <code>obj.SomeTimeConsumingMethod()</code>. </p>
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    1. POWhy should I always use || instead of | and && instead of &?
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    1. CO+1 But it would be great if you can add few lines or explain it!
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      1. USRahul Tripathi
    2. CODoes `|` and `&` not do it? How is this a reason?
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    3. CO@RahulTripathi, just added some details
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