A handshake is a short ritual in which two people grasp one of each other's like hands, in most cases accompanied by a brief up and down movement of the grasped hands.
Archaeological ruins and ancient texts show that handshaking was practiced in ancient Greece as far back as the 5th century BC; a depiction of two soldiers shaking hands can be found on part of a 5th century BC funerary stele on display in the Pergamon Museum, Berlin (stele SK1708) and other funerary steles like the one of the 4th century BC which depicts Thraseas and his wife Euandria handshaking (see images on the right).  The handshake is thought by some to have originated as a gesture of peace by demonstrating that the hand holds no weapon.
Modern customs 
There are various customs surrounding handshakes, both generically and specific to certain cultures:
The handshake is commonly done upon meeting, greeting, parting, offering congratulations, expressing gratitude, or completing an agreement. In sports or other competitive activities, it is also done as a sign of good sportsmanship. Its purpose is to convey trust, balance, and equality. If it is done to form an agreement, the agreement is only official until the hands are parted 
- In Anglophone countries, in business situations. In casual non-business situations, men are more likely to shake hands than women.
- In Switzerland, it may be expected to shake the women's hands first.
- Austrians shake hands when meeting, often including with children.
- In Russia, a handshake is rarely performed by opposite sexes. Man shaking hands with women can be considered impolite, since hand-kissing is preferred as a ritual for greeting a lady. However, kissing the hand is considered unsuitable for business situations.
- In some countries such as Turkey or the Arabic-speaking Middle East, handshakes are not as firm as in North America and Europe. Consequently, a grip which is too firm will be considered as rude.
- Moroccans also give one kiss on each cheek (to corresponding genders) together with the handshake. Also, in some countries, a variation exists where instead of kisses, after the handshake the palm is placed unto the heart.
- In China, where a weak handshake is also preferred, people shaking hands will often hold on to each other's hands for an extended period after the initial handshake.
- In Japan, it is appropriate to let the Japanese initiate the handshake, and a weak handshake is preferred.
- In Norway, where a firm handshake is preferred, people will most often shake hands when agreeing on deals, both in private and business relations.
- In South Korea, a senior person will initiate a handshake, where it is preferred to be weak. It is a sign of respect to grasp the right arm with the left hand when shaking hands.
- The Hand Hug is a type of handshake popular with politicians, as it can present them as being warm, friendly, trustworthy and honest. This type of handshake involves covering the clenched hands with the remaining free hand, creating a sort of "cocoon."
Atlantic City, New Jersey Mayor Joseph Lazarow was recognized by the Guinness Book of World Records for a July 1977 publicity stunt, in which the mayor shook more than 11,000 hands in a single day, breaking the record previously held by President Theodore Roosevelt, who had set the record with 8,510 handshakes at a White House reception on 1 January 1907.[dead link]
On Memorial Day 2008, two friends from Muscatine, Iowa, Kevin Whittaker and Cory Jens set the Guinness World Record for the world's longest handshake at 9 hours and 30 minutes in San Francisco, CA. On 21 September 2009, Jack Tsonis and Lindsay Morrison broke the Guinness World Record for the world's longest handshake, shaking hands for 12 hours, 34 minutes and 56 seconds. This record was broken less than a month later in Claremont, California, when John-Clark Levin and George Posner shook hands for 15 hours, 15 minutes, and 15 seconds. The next month, on 21 November, Matthew Rosen and Joe Ackerman surpassed this feat, with a new world record time of 15 hours, 30 minutes and 45 seconds., certified in the latest edition of the Guinness Book of Records on page 111. At 8pm EST on Friday 14 January 2011 the latest attempt at the longest hand-shake commenced in New York Times Square and the existing record was smashed  by semi-professional world record-breaker Alastair Galpin and Don Purdon from New Zealand and Nepalese brothers Rohit and Santosh Timilsina who agreed to share the new record after 33 hours and 3 minutes.
See also 
- Dap greeting
- Fist bump
- Golden handshake
- Greeting habits
- Handshake Man
- Handshaking lemma
- Holding hands
- Scout handshake
- Thomas, Chris (27 August 2009). "Handshake - Priest and two soldiers, 500BC. Pergamon Museum Berlin (SK1708)". Picasa Web Albums. Google. Retrieved 4 September 2011.
- Busterson, Philip A. Social Rituals of the British.
- "Dear Uncle Ezra - Questions for Tuesday, April 3, 2007". Cornell University. 3 April 2007. Question 8. Retrieved 4 September 2011. "There are many conflicting theories about the origin of the handshake. It seems that the most common one involves the evidence of the lack of a weapon in the right hand, which normally bears a weapon. It is shown to be empty by its connectedness to the opposite person's hand."
- Evergreen.edu 4 December 2002[unreliable source?]
- csun.edu -28 August 2002[unreliable source?]
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- Post, Emily (1922). Etiquette in Society, in Business, in Politics and at Home. New York: Funk & Wagnalls. Chapter 3.
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- Theconnectedwoman.com - "Handshakes from Around the World"
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- DeAngelis, Martin (4 January 2008). "Joseph Lazarow, who led Atlantic City through start of casino era, dies at 84". The Press of Atlantic City. Retrieved 4 January 2008.[dead link]
- McClymont, Mhairi (21 September 2009). "Great shakes! World record raises charity funds". ABC News. Retrieved 9 September 2011.
- "World's Longest Handshake".[dead link]
- "Movers and shakers - an article on the new World Record". The Jewish Chronicle Online. 3 December 2009. Retrieved 9 September 2011.
- "Longest Handshake: Team New Zealand and Team Nepal set world record". Worldrecordsacademy.org (New York, NY). 18 January 2011. Retrieved 4 September 2011.
- Galpin, Alastair. "Records achieved". WorldRecordChase.com. Longest continuous handshake. Retrieved 4 September 2011.
- "Kiwis break world record for a handshake". TVNZ.co.nz. Television New Zealand Limited. 17 January 2011. Retrieved 9 September 2011.
- "World record handshake holders". TVNZ.co.nz. Television New Zealand Limited. 19 January 2011. Retrieved 9 September 2011.
- Allheadlinenews.com[dead link]