Top-down and bottom-up design

Top-down and bottom-up are both strategies of information processing and knowledge ordering, used in a variety of fields including software, humanistic and scientific theories (see systemics), and management and organization. In practice, they can be seen as a style of thinking and teaching.

A top-down approach (also known as stepwise design and in some cases used as a synonym of decomposition) is essentially the breaking down of a system to gain insight into its compositional sub-systems in a reverse engineering fashion. In a top-down approach an overview of the system is formulated, specifying but not detailing any first-level subsystems. Each subsystem is then refined in yet greater detail, sometimes in many additional subsystem levels, until the entire specification is reduced to base elements. A top-down model is often specified with the assistance of "black boxes", these make it easier to manipulate. However, black boxes may fail to elucidate elementary mechanisms or be detailed enough to realistically validate the model. Top down approach starts with the big picture. It breaks down from there into smaller segments.

Top-down (disambiguation)

Top-down is a design strategy of information processing and knowledge ordering.

Top-down may also refer to:

Science

Computing

See also

Top Down

"Top Down" is a song by American hip hop record producer and recording artist Swizz Beatz. Featured as the eighth track on his debut studio album One Man Band Man. "Top Down" contains samples of swirls and riotous bursts of 70s-soul horns from "Girl, Come on Home" by Major Lance.

Background

In an interview with MTV Swizz Beatz explained the song was initially meant for Nas: "The record was originally for Nas. I got Nas' vocals already. But I can't do Nas, and his energy is not right on there. It would be dead weight. No disrespect, but it can't be dead weight if I can't make it feel like reality. I need the shit crazy. I need to shoot a video! It's gotta be another 'It's Me Bitches,' but bigger. I could easily pull a Nas card and have people be like, 'Nas is spazzing on the verse.' But it has to be a movie. I got it. It just gotta make sense. I can get Nas, Jay-Z and Jadakiss on that. I can do that. It's light work, but it's gotta make sense."

On May 30, 2009 the song Nas recorded over the beat leaked entitled "Be Worried".