A bitmap is a computer picture kept as a grid of tiny dots. Imagine graph paper: each little square is one point of colour, and the computer stores a number for every square.

A bitmap is a computer picturebitmap（點陣圖）是一種電腦圖像， kept as a grid of tiny dots用一格一格的小點存起來。 Imagine graph paper想像方格紙： each little square is one point of colour每一個小格子是一個色點， and the computer stores a number for every square電腦會替每一格存一個數字。

In the oldest kind, that number may be a single bit — just on or off, black or white. Colour pictures use a bundle of bits for each square.

In the oldest kind在最早的形式裡， that number may be a single bit那個數字可能只是一個位元—— just on or off, black or white不是開就是關，非黑即白。 Colour pictures use a bundle of bits for each square彩色圖片則是每一格用一整組位元。

Zoom in far enough and you see those squares; that is the giveaway. The other common way to keep a picture is as lines and shapes (a vector image), which stays sharp when you make it bigger. A bitmap does not.

Zoom in far enough and you see those squares放大到一定程度，你就會看到那些格子； that is the giveaway這就是破綻所在。 The other common way to keep a picture is as lines and shapes (a vector image)另一種常見的存圖方式，是用線條和形狀來存（也就是向量圖）， which stays sharp when you make it bigger放大之後還是一樣清晰。 A bitmap does notbitmap則不會。

Though actually, in everyday talk people say “bitmap” for almost any pixel picture — a photo, a screenshot, even a PNG or JPEG — not only the old .bmp file. Programmers also use it for a grid of bits that is not a picture at all, just packed yes/no flags.

Though actually, in everyday talk people say “bitmap” for almost any pixel picture不過話說回來，日常講話時人們幾乎會把任何點陣圖片都叫做「bitmap」—— a photo, a screenshot, even a PNG or JPEG照片、截圖，甚至PNG或JPEG檔—— not only the old .bmp file不只是舊式的.bmp檔案。 Programmers also use it for a grid of bits that is not a picture at all程式設計師也會用這個字來指一整格根本不是圖片的位元， just packed yes/no flags只是打包起來的是非旗標。

Ordinary in computing; you would not use it about a painting on a wall.

Ordinary in computing在電腦領域是很平常的字； you would not use it about a painting on a wall你不會用它來說牆上的一幅畫。