What Is An Array In Computer Science

Learn the definition of an array in computer science. Understand this fundamental data structure for storing collections of elements with clear examples.

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What Is an Array?

An array is a fundamental data structure in computer science that stores a collection of elements, all of the same data type, in a contiguous block of memory. Each element in the array is identified by a numerical index or key, which represents its position within the collection.

Section 2: Key Components of an Array

The primary components of an array are its elements and indices. The elements are the actual data values stored in the array (e.g., numbers, characters). The index is the position of an element, which almost always starts at 0 for the first element, 1 for the second, and so on. Most basic arrays are also of a fixed size, meaning the number of elements they can hold is determined when the array is created.

Section 3: A Practical Example

Imagine you want to store the daily high temperatures for a week. You could use an array of integers like this: `[75, 78, 81, 79, 85, 88, 86]`. To access the temperature for the first day, you would use index 0, which holds the value 75. To get the third day's temperature (81), you would use index 2.

Section 4: Why Are Arrays Important?

Arrays are incredibly important because they provide a highly efficient way to store and access ordered data. Because the elements are stored together in memory, accessing any element by its index is extremely fast. They form the basis for many other complex data structures and are used extensively in algorithms for sorting, searching, and managing data.

Frequently Asked Questions

What is the difference between an array and a list?
Why do array indexes usually start at 0?
What is a multi-dimensional array?
Is it slow to add or remove elements from an array?