Whether you're preparing for an interview or busy writing and executing codes, there are instances when you come across a situation that needs you to have a fair idea that sets a "for" loop apart from a "while" loop. To be honest, the scene can be heavily confusing for many. But luckily not anymore. 

How is a for loop different from a while loop?

The prime thing that sets for loop and while loop apart is their overall nature. In the case of for loop, you as a coder will be aware of the number of iterations that need to be used in attaining a particular result. On the contrary, the while loop statement needs to be executed until it reaches a condition and proves the statement false. 

But wait, there is more to it. Walk through the entire article to learn more.

What is a For Loop?

With for loop, you're looking at a control flow statement that allows users to execute codes repeatedly for specifying an iteration. In other words, for loop is a statement used to check specific conditions and then execute a set of codes until the required condition is met.

What is a While Loop?

The term while loop refers to the most fundamental loop in coding. It comes into existence when the command in focus iterates an uncertain number of times until the condition becomes true. The condition, in this case, is generally any Boolean expression.

Difference Between For Loop and While Loop

Syntax

For Loop: for (initialization; condition; iteration)

{

//body of for loop

}

While Loop: while (condition)

{

Statements: //body of loop

}

Initialization

In the case of "for loop," the initialization can either be inside or outside the loop, whereas "while loop" always sees initialization outside.

Increment Time

In "for loop," increment is done only after the statement is executed. On the contrary, the "while loop" is comparatively  flexible and can be incremented before or after the execution.

Condition

For loop, the condition is generally a relational expression. At the same time, you can expect an expression or a non-zero value as a condition in the "while loop. In other words, for loop comprises a single condition, while the same for a while loop is an entire set at a time.

Time of Use

For loop is usually used when the number of iterations are known. While loop, on the other hand, comes into aid when you're unaware of the number of iterations.

Absence of Condition

Suppose the condition goes missing in for loop, the loop sets into an iteration mode for infinite repetitions. A missing condition in the while loop displays an error.

Initialization and Increment Nature

For loop is helpful whenever the initialization alongside the increment is simple. The scenes are entirely different in the while loop. The latter is used for initialization which is complex in nature.

Comparison Chart: For Loop Vs. While Loop

ParameterFor LoopWhile Loop
Syntaxfor (initialization; condition; iteration){//body of for loop}while (condition){Statements: //body of loop}
InitializationCan either be inside or outside the loopAlways outside the loop
Increment TimeAfter the statement is executedBefore or after the execution of statement
ConditionRelational expressionAn expression or non zero value
Time of UseWhen the number of iterations are knownWhen the number of iterations are unknown
Absence of ConditionGoes into interaction mode for infinite repetitionsDisplays error
Initialization and Increment NatureSimpleComplex

Similarities: How For Loop is Similar to While Loop?

Besides being fairly apart, both “for” and “while” loops have one thing in common. Whether it is for loop or while loop, both proceed after checking the condition at the time of entry. To put it in simple words, for loop and while loop are generally entry controlled loops. 

Frequently Asked Questions

What are Loops?

In the world of programming languages, loops are a set of statements for iterations. The prime purpose of these loops is to allow a group of instructions to get repeatedly executed until and unless any specific condition is true. The loop generally displays an error or terminates as soon as the statement is false.

Why use a do-while loop vs. a while loop vs. a for loop?

Do while loop, while loop, and for loop functions differently altogether. In the case of do-while, the condition in focus gets checked only after concluding all the executions. In contrast, the same is checked at the initial level in the while loop. For loop involves the checking of conditions explicitly within the syntax itself. So depending on your requirements, use do-while, while, and for loop accordingly.

Which is better for loop or while loop?

There is no way you can distinguish the for loop and the while loop in the efficiency section. It entirely depends upon the resources you have under a particular situation. For instance, if you're aware of the number of times you need to run the loop, "for loop" is the promising choice; elsewhere, you must go for the "while loop."

Conclusion

With that, we’re done talking about the primary distinguishing factors between for loop and while loop. Alongside these elements, we’ve also tracked down the nature that sits similar in both of them. Suppose you’re someone who has been meeting trouble figuring out the proper manner of inputting the loops as mentioned earlier in distinct locations. In that case, we recommend you read the entire article and inculcate a more fair idea.

Do you have more things to look at? Let us know in the comment section.

Sources

https://en.wikipedia.org/wiki/For_loop

https://en.wikipedia.org/wiki/While_loop

https://www.cs.utah.edu/~germain/PPS/Topics/for_loops.html

https://www.cs.utah.edu/~germain/PPS/Topics/while_loops.html