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How can we describe conditional statements in software and hardware? This lecture introduces you to
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simple implementations of conditional statements in software and hardware.
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A conditional statement has two parts: hypothesis and conclusion. If the hypothesis is correct, then 
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the conclusion will occur.  
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In a software program, usually, an if-then structure is used to describe a condition. An if-then 
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structure usually has two parts: a boolean expression or hypothesis and a block containing a consequence
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or conclusion.
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In a general case of the conditional statement, a selection between a consequence and its alternative
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may happen.
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If the Boolean expression is true, then the consequence block is selected; 
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otherwise, the alternative part will be chosen.
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In logic design, a switch can implement the conditional statement. In the simplest form, a select bit 
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controls the switch and the connection between the input and output bits.
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If the select bit is 0, the input is not connected to the output. Otherwise, the output is the input. 
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In the generalized form, the switch can select between two or more options.
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For example, if the select bit is zero, the first input is connected to the output, 
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and if it is one the output in the second input.
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How can we use logic gates to implement conditional statements? To cope with this question, 
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I will explain the concept of a multiplexer and its implementation with logic gates in the next lecture. 
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These are our takeaway messages: Each decision-making process has at least one Hypothesis and one Conclusion. 
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If the hypothesis is correct, then the conclusion will occur.  If statements in software and switches 
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in hardware are the building blocks of decision-making processes.
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Now the quiz question. How can we use the following hardware switches to implement a decision-making process 
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with four options for selection?