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Part I ✦ Welcome to Photoshop
the hearts and minds of the digital art community. Meanwhile, other vendors have
had to devote smaller resources to playing catch-up. Some, such as Jasc Software,
with its Windows-only Paint Shop Pro, have hung in there and remained commer-
cially viable. But such success stories are few and far between. Although competi-
tors have provided some interesting and sometimes amazing capabilities, the sums
of their parts have more often than not fallen well short of Photoshop’s.
As a result, Photoshop rides a self-perpetuating wave of market leadership. It wasn’t
always the best image editor, nor was it the first. But its deceptively straightforward
interface combined with a few terrific core functions made it a hit from the moment
of its first release. More than a dozen years later — thanks to substantial capital
injections from Adobe and highly creative programming on the parts of Photoshop’s
engineering staff and its originator, Thomas Knoll — Photoshop has evolved into
the most popular program of its kind.
Image-Editing Theory
Like any image editor, Photoshop enables you to alter photographs and other
scanned artwork. You can retouch an image, apply special effects, swap details
between photos, introduce text and logos, adjust color balance, and even sharpen
the focus of a photograph. Photoshop also provides everything you need to create
artwork from scratch, including a suite of vector drawing tools and a highly special-
ized painting palette. These tools are fully compatible with pressure-sensitive tablets,
so you are not limited to creating only those images you can successfully draw with
a mouse.
Bitmaps versus vectors
Image editors fall into the larger software category of painting programs. In a painting
program, you draw a line, and the application converts it to a string of tiny square
dots called pixels. The painting itself is called a bitmapped image, but bitmap and
image are equally acceptable terms.
Photoshop uses the term bitmap exclusively to mean a black-and-white image, the
logic being that each pixel conforms to one bit of data, 0 or 1 (off or on). To avoid
confusion — and because forcing a distinction between working with exactly two
colors or anywhere from 4 to 16 million colors is entirely arbitrary — the term
bitmap is used more broadly to mean any image composed of a fixed number of
pixels, regardless of the number of colors involved.
What about other graphics applications, such as Adobe’s own Illustrator? Applica-
tions such as Illustrator, Macromedia FreeHand, and CorelDraw fall into a different
category of software called drawing programs. Drawings comprise vector objects,
which are independent, mathematically defined lines and shapes. For this reason,
drawing programs are sometimes said to be vector-based or object-oriented.
Note
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