reading-notes

Comparison and logical operators

You may be familiar with comparison operators from math class. Let’s make sure there aren’t any gaps in your knowledge.

Comparison Operators

• Less than (<) — returns true if the value on the left is less than the value on the right, otherwise it returns false.
• Greater than (>) — returns true if the value on the left is greater than the value on the right, otherwise it returns false.
• Less than or equal to (<=) — returns true if the value on the left is less than or equal to the value on the right, otherwise it returns false.
• Greater than or equal to (>=) — returns true if the value on the left is greater than or equal to the value on the right, otherwise it returns false.
• Equal to (===) — returns true if the value on the left is equal to the value on the right, otherwise it returns false.
• Not equal to (!==) — returns true if the value on the left is not equal to the value on the right, otherwise it returns false.

Logical Operators

Comparison operators allow us to assert the equality of a statement with JavaScript. For example, we can assert whether two values or expressions are equal with ===, or, whether one value is greater than another with >.

There are scenarios, however, in which we must assert whether multiple values or expressions are true. In JavaScript, we can use logical operators to make these assertions.

&& (and) — This operator will be truthy (act like true) if and only if the expressions on both sides of it are true. || (or) — This operator will be truthy if the expression on either side of it is true. Otherwise, it will be falsy (act like false).

While loop

The while loop loops through a block of code as long as a specified condition is true.

while (condition) {
  // code block to be executed
}

For loop

The for loop has the following syntax:

for (statement 1; statement 2; statement 3) {
  // code block to be executed
}

Thank you