Array
Names and abbreviations on this page
MDN — MDN Web Docs (formerly Mozilla Developer Network). Reference material for web programming.
Programming terms & practical skills
What it means
An array is an indexed collection of values. Many languages number the first position as zero, though rules differ. Arrays help organize a sequence such as expense amounts, search results or completed tasks.
Related skills
Read positionsUnderstand the language's indexing rules.
Process collectionsUse iteration to examine each entry.
Preserve meaningKeep related labels and values associated when sorting or filtering.
An everyday example
A small practice array can hold three expense amounts: 1200, 150 and 50. Processing each amount once gives a total of 1400. Check that removing an entry changes the result as expected.
What to check
Array length and the final valid index are often different. Empty arrays need intentional handling.