Before this lesson, our code executed from top to bottom, line by line.

Conditional statements add branching paths to our programs. We use conditionals to make decisions in the program so that different inputs will produce different results.

Conditionals have the general structure:

if (condition) {
    // consequent path
} else {
    // alternative path
}

Specific conditional statements have the following behavior:

• if-then:
  • code block runs if condition is true
• if-then-else:
  • one block runs if conditions is true
  • another block runs if condition is false
• if-then-else chained:
  • same as if-then but an arbitrary number of conditions
• switch:
  • switch block runs if condition value matches case value