World Cup qualifiers

The FIFA World Cup qualification is the process that a national association football team goes through to qualify for the FIFA World Cup finals. The FIFA World Cup is the largest international team sport competition in the world with a qualification process required to reduce the large field of countries from 211 to just 32 for the World Cup finals until the 2022 edition.

Qualifying tournaments are held within the six FIFA continental zones (Africa, Asia, North and Central America and Caribbean, South America, Oceania, Europe), and are organized by their respective confederations. For each tournament, FIFA decides beforehand the number of places in the finals allocated to each of the continental zones, based on the numbers or relative strength of the confederations' teams.

The hosts of the World Cup receive an automatic berth. Unlike many other sports, results of the previous World Cups or of the continental championships are not taken into account. Until 2002, the defending champions also received an automatic berth, but starting from the 2006 World Cup this is no longer the case.

The current qualification process is the 2018 FIFA World Cup qualification which commenced in 2015 and will finish in late 2017.

Over many years, the World Cup's qualification has evolved, from having no qualification at all in 1930, when the tournament was invitational and only 13 teams entered, to the current two-year process. The first World Cup qualifying match was played on 11 June 1933 when Sweden defeated Estonia 6–2 in Stockholm. The first ever goal in a World Cup qualifying match was scored 7 minutes into the game: it was scored according to some sources by Swedish captain Knut Kroon, or according to other sources by Estonian goalkeeper Evald Tipner (own goal).

While the number of teams which qualified for the finals has increased steadily, from 16 between 1934 and 1978, to 24 between 1982 and 1994, and finally to 32 starting from 1998, the qualification format has been basically the same throughout the history of the World Cup. The teams have been grouped continentally, and they competed for a fixed number of places, with one or two places awarded to the winners of intercontinental play-offs.

...
Wikipedia