rækker

Rækker is the plural of the Danish noun række, meaning a line or row of objects arranged in a direction. It is used for rows of seats, books on a shelf, or crops in a field, among other contexts. The term can also refer to a sequence or ordered progression of items, such as a row of numbers or dates.

In mathematics, række can denote a sequence of numbers (talrække) or a series when its terms are added together. A geometrisk række refers to a geometric series. The distinction between sequence and series is made by context, with række often used for an ordered list and serie or geometrisk række for a sum.

In data handling and computing, rækker describe the horizontal lines of elements in a matrix, table, or spreadsheet. For a matrix, each horizontal line of elements is a row; the vertical lines are columns (kolonner).

Etymologically, rekke derives from Old Norse rekka, meaning line, rank, or chain, and is related to the general sense of lining things up. In Danish, phrases such as i rækkefølge (in order) or på række (in a row) reflect the broad sense of orderly arrangement.