Unit 5 Lesson 3: Introduction to Arrays CS Principles

Unit 5 Lesson 3: Introduction to Arrays Students will be able to: Identify an array as a data structure used to store lists of information in programs. Create arrays and access information stored within them using an index. Manipulate an array using the append, insert, and remove operations. Account for the fact that JavaScript arrays are zero- indexed when using them in a program.

Introduction to Arrays Some sort of list data structure is a component of almost all programming languages. A list allows large amounts of information to be easily referenced and passed around a program, and the use of a numeric index allows individual items in a list to be accessed. Historically a list would have literally been a single contiguous chunk of memory and the index or address was used to know how far into that chunk a relevant piece of information was stored. In many modern languages, however, it is more likely that the items in an array are stored at many locations on your computer’s hard drive In this way, a JavaScript array is actually another example of abstraction. We know that it is holding a list of related information, but we don’t need to think about the actual implementation details.

U5L13 Vocab Array - A data structure in JavaScript used to represent a list. List - A generic term for a programming data structure that holds multiple items.

U5L13 Prompt "Today we’re going to start looking at how we can use lists in programs, but before we dive into that, let’s think about why we would want to in the first place. What are the benefits of creating lists? Why is it helpful to keep information in lists?" Prompt: What makes lists useful in everyday life?

Transition to Code Studio Go to U5L13 in Code Studio. Day 1 (Tuesday) Complete through AT LEAST Stage 7 (parts I & II ) Day 2 (Wednesday) Complete through Stage 31 (parts III & IV)