Chinese characters can be written according to five major styles. These styles are intrinsically linked to the history of Chinese script.
Seal Script
The seal script (often called small seal script or 小篆Xiǎozhuàn is the formal script of the Qín system of writing, which evolved during the Eastern Zhōu dynasty in the state of Qín and was imposed as the standard in areas Qín progressively conquered. Beginning around the Warring States period, it became vertically elongated with a regular appearance. This was the period of maturation of Small Seal script, also called simply seal script. It was systematized by Li Si during the reign of the First Emperor of China Qin Shi Huang through elimination of most variant structures, and was imposed as the nationwide standard (thus banning other regional scripts), but small seal script was clearly not invented at that time. Through Chinese commentaries, it is known that Li Si compiled Cangjie, a non-extant work of character recognition listing some 3,300 Chinese characters in small seal script. Their form is characterised by being less rectangular and more squarish.
Although some calligraphers now practice the most ancient oracle bone script as well as various other scripts older than seal script found on Zhōu dynasty bronze inscriptions, seal script is the oldest style that continues to be widely practiced. Today, this style of Chinese writing is used predominantly in seals, hence the English name. Although seals (name chops), which make a signature-like impression, are carved in wood, jade and other materials, the script itself was originally written with brush and ink on bamboo books and other media, just like all other ancient scripts.
Most people today cannot read the seal script, so it is considered an ‘ancient’ script, generally not used outside the fields of calligraphy and carved seals. However, because seals act like legal signatures in Chinese culture, Korean culture, Vietnamese culture and Japanese culture, and because vermilion seal impressions are a fundamental part of the presentation of works of art such as calligraphy and painting, seals and therefore seal script remain ubiquitous.
http://en.wikipedia.org/wiki/File:XiaozhuanQinquan.jpg

Clerical Script
The clerical script (often simply termed lìshū; and sometimes called official, draft or scribal script) is popularly thought to have developed in the Hàn dynasty and to have come directly from seal script, but recent archaeological discoveries and scholarship indicate that it instead developed from a roughly executed and rectilinear popular or ‘vulgar’ variant of the seal script as well as from seal script itself, resulting first in a ‘proto-clerical’ version in the Warring States period to Qín Dynasty [1], which then developed into clerical script in the early Western Hàn dynasty, and matured stylistically thereafter. In general, characters are often "flat" in appearance, being wider than the preceding seal script and the modern standard script, both of which tend to be taller than they are wide; some versions of clerical are square, and others are wider. Compared with the preceding seal script, forms are strikingly rectilinear; however, some curvature and some seal script influence often remains. Seal script tended towards uniformity of stroke width, but clerical script gave the brush freer rein, returning to the variations in width seen in early Zhōu brushwork. Most noticeable is the dramatically flared tail of one dominant horizontal or downward-diagonal stroke, especially that to the lower right. This characteristic stroke has famously been called 'silkworm head and wild goose tail' (蚕头雁尾 cántóu yànwěi)in Chinese due to its distinctive shape.
The archaic clerical script or ‘proto-clerical’ of the Chinese Warring States period to Qín Dynasty and early Hàn Dynasty can often be difficult to read for a modern East Asian person, but the mature clerical script of the middle to late Hàn dynasty is generally legible. Modern calligraphic works and practical applications (e.g., advertisements) in the clerical script tend to use the mature, late Hàn style, and may also use modernized character structures, resulting in a form as transparent and legible as regular (or standard) script. The clerical script remains common as a typeface used for decorative purposes (for example, in displays), but other than in artistic calligraphy, adverts and signage, it is not commonly written.
http://en.wikipedia.org/wiki/File:Clerical_Eg.png)

Semi-cursive Script
The semi-cursive script (also called running script,行书xíngshū). It is derived from clerical script, and was for a long time after its development in the first centuries AD the usual style of handwriting. It approximates normal handwriting in which strokes and, more rarely, characters are allowed to run into one another. In writing in the semi-cursive script, the brush leaves the paper less often than in the regular script. Characters appear less angular and rounder. The characters are also more bold. Some of the best examples of xingshu calligraphy can be found in the work of Wang Xizhi (321-379) of the Eastern Jin Dynasty.
In general, an educated person in China or Japan can read characters written in the semi-cursive script with relative ease, but may have occasional difficulties with certain idiosyncratic shapes.
"Preface to the Poems Composed at the Orchid Pavilion" by Wang Xizhi (王羲之) http://en.wikipedia.org/wiki/File:LantingXu.jpg)

Cursive Script
The cursive script (sometimes called grass script,草书cǎoshū. Cursive script originated in China during the Han dynasty through Jin Dynasty period, in two phases. First, an early form of cursive developed as a cursory way to write the popular and not yet mature clerical script. Faster ways to write characters developed through four mechanisms: omitting part of a graph, merging strokes together, replacing portions with abbreviated forms (such as one stroke to replace four dots), or modifying stroke styles. This evolution can best be seen on extant bamboo and wooden slats from the period, on which the use of early cursive and immature clerical forms is intermingled. This early form of cursive script, based on clerical script, is now called zhāngcǎo (章草), and variously also termed ancient cursive, draft cursive or clerical cursive in English, to differentiate it from modern cursive (今草 jīncǎo). Modern cursive evolved from this older cursive in the Wei Kingdom to Jin dynasty with influence from the semi-cursive and standard styles.)
 It is a fully cursive script, with drastic simplifications requiring specialized knowledge; a person who can read the semi-cursive script cannot be expected to read the cursive script without training. Entire characters may be written without lifting the brush from the paper at all, and characters frequently flow into one another. Strokes are modified or eliminated completely to facilitate smooth writing and to create a beautiful, abstract appearance. Characters are highly rounded and soft in appearance, with a noticeable lack of angular lines. Due to the drastic simplification and ligature involved, this script is not considered particularly legible to the average person, and thus has never achieved widespread use beyond the realm of literati calligraphers.
The cursive script is the source of Japanese hiragana, as well as many modern simplified forms in Simplified Chinese characters and Japanese shinjitai.
http://en.wikipedia.org/wiki/File:Treatise_On_Calligraphy.jpg

Regular Script
The regular script (often called ‘standard script’ or simply ‘kǎishū’楷书) is one of the last major calligraphic styles to develop, emerging between the Chinese Hàn dynasty and Three Kingdoms period, gaining dominance in the Southern and Northern Dynasties, and maturing in the Táng Dynasty.
Standard script came into being between the Eastern Hàn and Cáo Wèi dynasties, and its first known master was Zhōng Yáo (sometimes also read Zhōng Yóu; 在钟繇), who lived in the Hàn to Cáo Wèi period, He is known as the “father of standard script”, and his famous works include the Xuānshì Biǎo (宣示表), Jiànjìzhí Biǎo (荐季直表), and Lìmìng Biǎo (力命表).
It emerged from a neatly written, early period semi-cursive form of clerical script. As the name suggests, the regular script is "regular", with each of the strokes placed slowly and carefully, the brush lifted from the paper and all the strokes distinct from each other.
The regular script is also the most easily and widely recognized style, as it is the script to which children in East Asian countries and beginners of East Asian languages are first introduced. For learners of calligraphy, the regular script is usually studied first to give students a feel for correct placement and balance, as well as to provide a proper base for the other, more flowing styles.
In the regular script samples to the right, the characters in the left column are in Traditional Chinese while those to the right are in Simplified Chinese.
It is better to attach a picture of this script.(you can refer to ”Chu Suiliang (褚遂良) Sheng Jiao Xuhttp://en.wikipedia.org/wiki/File:Sheng_jiao_xu.jpg)