What is the difference between by elections and general elections?

Answer 1

A general election takes place when every elected seat in a body - for example, a chamber of a legislature - is up for election at once, simultaneously, in the same election period, though not necessarily on the same day. For example, on May 6 2010, the United Kingdom held a general election when all 650 of its Members of Parliament were elected at once.

In contrast, a by-election is held to fill an arising vacancy on a body. If a member dies, resigns or is expelled from a legislative body, in most jurisdictions, a by-election is held to replace that person with a new member, who serves until the next general election. Even if multiple by-elections take place at once, they do not constitute a general election, though they usually occur only in small groups or on their own. For example, in the UK, by-elections will be held to fill three vacancies in the House of Commons on November 15 2012.

An example of a large number of by-elections being held together outside of a general election would be the Burmese by-elections of April 1 2012, when 46 seats (out of 664) were elected at once as the result of vacancies in the Assembly of the Union.