The Vostok was a type of spacecraft

Spacecraft

A spacecraft or spaceship is a craft or machine designed for spaceflight. Spacecraft are used for a variety of purposes, including communications, earth observation, meteorology, navigation, planetary exploration and transportation of humans and cargo....

 built by the Soviet Union

Soviet Union

The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....

. The first human spaceflight

Human spaceflight

Human spaceflight is spaceflight with humans on the spacecraft. When a spacecraft is manned, it can be piloted directly, as opposed to machine or robotic space probes and remotely-controlled satellites....

 in history was accomplished on this spacecraft on April 12, 1961

Cosmonautics Day

Cosmonautics Day is a holiday celebrated in Russia and some other former USSR countries on April 12. This holiday celebrates the first manned space flight made on April 12, 1961 by the 27-year old Soviet cosmonaut Yuri Gagarin. Gagarin circled the Earth for 1 hour and 48 minutes aboard the Vostok...

, by Soviet cosmonaut Yuri Gagarin

Yuri Gagarin

Yuri Alekseyevich Gagarin was a Soviet pilot and cosmonaut. He was the first human to journey into outer space, when his Vostok spacecraft completed an orbit of the Earth on April 12, 1961....

.

The spacecraft was part of the Vostok programme

Vostok programme

The Vostok programme was a Soviet human spaceflight project that succeeded in putting a person into Earth's orbit for the first time. The programme developed the Vostok spacecraft from the Zenit spy satellite project and adapted the Vostok rocket from an existing ICBM design...

 in which six manned spaceflights were made from 1961 to 1963. Two further manned space flights were made in 1964 and 1965 by Voskhod spacecraft, which were modified Vostok spacecraft. By the late 1960's both were superseded by the Soyuz spacecraft, which are still used as of 2011.
The Vostok spacecraft was originally designed for use both as a camera platform (for the Soviet Union's first spy satellite program, Zenit

Zenit spy satellite

Zenit is the name of a series of military spy satellites launched by the Soviet Union between 1961 and 1994. To conceal their nature, all flights were given the public Kosmos designation...

) and as a manned spacecraft.