Computers

A computer desk hutch is a sort of raised area that goes on the top of a computer desk. The monitor will sit in front of it and the body of the computer will, typically, go below. There will be drawers or cabinets built into the hutch, which is why many people love them. They offer a lot of space in which things can be stored that are needed when working with a computer. These things will all be close at hand, making it so that you do not have to walk to a closet every time that you need something, but they will not look like clutter, piled all around on the desk's top. You will be able to tuck them away where they will not be seen unless someone is looking for them. There are many different things that can be stored in a computer desk hutch.

First off, you will want to store all of the extra cables and cords that go with the computer. These need to be close because you could need them at any time -- you might not need a USB cable until your friend stops by and wants to hook his camera up to your computer, for instance. You can also put extra power strips and electrical cords so that you can plug the computer in; this allows you to replace those things if they burn out.

Beyond that, you could put the typical things that you will need when doing business work. This could include envelopes, stamps, tape, paper, pens, paper clips, and many other things. You can image how bad these would look if they were just piled on top of the desk. By putting them in the hutch, you will not have to deal with that kind of clutter. If the drawers are large enough, you could even use the hutch to store tax information and other such documents.

A computer desk hutch is really just a way of making sure that you do not waste space. All of the space over the computer's monitor would just be empty if not for the hutch and the cabinets and drawers that it provides.

Advantages of using wizard

1. it's quicker

2. It's simple

Disadvantages

1. It's for beginners

2. It's time consuming

In any typical application (like desktop/personal computers), there would be two types of motors: brushless motors and stepper motors.

Brushless motors are usually used to run things that need to run without exact position control. These kind of motors are used in the computer cooling system (ie. cooling fans), and in some motive applications like optical media (driving the CD/DVD discs). These motors are generally a very good choice for two reasons: the don't have many parts that wear out (like brushed DC or AC motors), and their speed can be controlled rather precisely. These motors are driven with varying AC pulses (most commonly squares rather than sines), and usually have three leads (more rarely four) attached directly to the stator. If direct and precise speed regulation is not that important, they will usually just expose the positive and negative leads (typically red and black), keeping their driving electronics hidden inside the enclosure (in most cases - on a small disc-shaped PCB right under the rotor). They sometimes also expose a third lead for counting rotations, like cooling fans do (yellow wire). When mounted inside components (like DVDs), they are usually attached directly to the circuit board (typically glued/screwed in place). In most cases, these motors drive their load (fan, CD etc.) directly. They consist of many coils (how many - depends on construction) on the stator, and one permanent magnet on the rotor. When turned by hand, they usually turn freely.

Stepper motors are a more specific subset of brushless motors, giving much finer control of position, and they are generally much more precise. Stepper motors can also stop at a precisely defined position or turn only a precisely defined angle ("make a step", or halfstep etc. - thus "stepper" motors). These motors are used in optical media head drivers (ie. the motor that regulates where the reading/writing head is positioned), as well as floppy disk drives (very rare devices nowadays) and hard disks. These motors are also heavily used in inkjet/ribbon printers (printing head positioning), and in scanners (reading head positioning) - in general in all applications where invariability and precision are important. In most cases*, stepper motors drive their load (printing/reading heads etc.) indirectly through some form of a gearing mechanism - most notably a worm drive - to give finer control over the movement. They consist of many coils on the stator, and a matching set of small, powerful (rare earth) magnets on the rotor, thus enabling the stepping action. When turned by hand, they will show resistance and a tendency to "jump into" positions at regular intervals.

It is worth noting that while brushless motors do generate a lot of "chatter" on the power line (feedback from the driving mechanism, ie. noise on the line) while they spin, this is still nothing compared to brushed motors which can vary widely (and wildly). Also, brushless motor "chatter" can be predicted (and thus counteracted) with fair consistency.

* the most significant and commonplace deviation is the hard disk (HDD) platter drive. These stepper motors are used for their extremely precise speed control, and the platters are attached directly to them. These motors are designed with speed in mind as well (typically running at 7200 revolutions per minute, sometimes higher), but their fine speed and position control is used to make sure that the platter is in the correct "reading" position when the reading head is in the correct "reading" position as well, at those high speeds.

John Von Neumann's: One shared memory for instructions (program) and data with one data bus and one address bus between processor and memory. Instructions and data have to be fetched in sequential order (known as the Von Neumann Bottleneck), limiting the operation bandwidth. Its design is simpler than that of the Harvard architecture. It is mostly used to interface to external memory.
explain correctly what is von neumann concept?
an automatic programmable computer using a single shared common memory for storing both instructions and data.

This is in contrast to Harvard Architecture, which is an automatic programmable computer using two physically separate memories for storing instructions and data.

Most modern computers use a mixture of both: the CPU itself is Harvard, getting instructions and data from two physically separate caches; but the system as a whole is von Neumann, loading both caches from a single common shared memory.