Classification Essay
In a classification essay, we organize things into categories and give examples of things that fit into each category. For example, if you choose to write about types of computers (PCs and servers), each of your developmental paragraphs will define the characteristics of a different computer type.
Classification criteria:
Before writing, it is necessary to decide on the classification criteria. We should think according to what properties we are going to classify things. The criteria must be discriminating and the emerging classes should be non-overlapping.
In the sample essay about types of computers, the computers are classified according to their functions and capabilities, as:
Sample essay analysis
Topic: Type of computer
Criteria: Functions
1. PC
general use by a single person
desktop: permanent
laptop: portable
2. Workstation
used for 3D graphics, game development
powerful microprocessor, additional memory and enhanced capabilities
3. Server
used to provide services to other computers
have powerful processors, lots of memory and large hard drives
4. Main frame
used in business
enables hundreds of people to work together
5. Super computer
used for jobs that take massive amounts of calculating
very powerful
The introduction of a classification essay is quite straightforward. In the thesis statement, writers mention that there are (number) types of (something) according to their (properties).
In the developmental paragraphs, define each type mentioned in the thesis. Students may also need to show the similarities and/or differences of these types. Giving examples enables the readers to understand better.
The common transitions used while classifying are the first kind / type / group, the second kind / type / group, the third kind / type / group.

Sample classification essay: Types of Computers
There are a lot of terms used to describe computers. Most of these words imply the size, expected use or capability of the computer. While the term “computer” can apply to virtually any device that has a microprocessor in it, most people think of a computer as a device that receives input from the user through a mouse or keyboard, processes it in some fashion and displays the result on a screen. Computers can be divided into five according to the purpose they are used for and their capabilities.
The most familiar type of microprocessor is the personal computer (PC). It designed for general use by a single person. While a Mac is also a PC, most people relate the term with systems that run the Windows operating system. PCs were first known as microcomputers because they were a complete computer but built on a smaller scale than the huge systems in use by most businesses. A PC can come in two types (three if we include the Personal Digital Assistants (PDAs) that differ from PCs not by the working policy but in appearance as well.): Desktop and laptop. The former is not designed for portability. The expectation with desktop systems is that you will set the computer up in a permanent location. Most desktops offer more power, storage and versatility for less cost than their portable brethren. On the other hand, the laptops – also called notebooks – are portable computers that integrate the display, keyboard, a pointing device or trackball, processor, memory and hard drive all in a battery-operated package slightly larger than an average hardcover book.
Another purpose for using a microprocessor is as a workstation. The computers used for this purpose have a more powerful processor, additional memory and enhanced capabilities for performing a special group of task, such as 3D Graphics or game development.
A computer can also be used as a server. For this, it needs to be optimized to provide services to other computers over a network. Servers usually have powerful processors, lots of memory and large hard drives.
A fourth type, a main frame is the heart of a network of computers or terminals which allows hundreds of people to work at the same time on the same data. It is indispensable for the business world.
Sometimes, computers can be used for specialized fields as well. The super computer is the top of the heap in power and expense. It is used for jobs that take massive amounts of calculating, like weather forecasting, engineering design and testing, serious decryption, and economic forecasting.
With the increasing demand in different specialties, new adjustments are being made to microprocessors and new types of computers that serve different purposes emerge. In this ongoing process, it would not possible to put a full stop here. What we suggest is that it is better to keep en eye on the development of science in this field and keep updating our knowledge in order not to be out-of-date like the computers of old times that were as big as a room.
Adapted from: Bogazici University SFL

Written by Oya Ozagac, May 2004