Editing Space Invaders (section)

==Gameplay==
[[File:SpaceInvaders-Gameplay.gif|thumb|left|alt=A vertical rectangular video game screenshot that is a digital representation of a battle between aliens and a laser cannon. The white aliens hover above four green, inverted U-shaped blocks. Below the blocks is a smaller horizontal block with a triangle on its top.|The player-controlled laser cannon (bottom center) shoots the aliens (center) as they descend. Game statistics, like the current score and remaining lives, are tracked above and below the playing field.]]

''Space Invaders'' is a [[fixed shooter]] in which the player moves a [[laser cannon]] horizontally across the bottom of the screen and fires at aliens overhead. The aliens begin as five rows of eleven that move left and right as a group, shifting downward (advancing on the shooter) each time they reach a screen edge. The goal is to eliminate all of the aliens by shooting them. Regardless of how many lives remaining the player has, the game ends immediately if the invaders reach the bottom of the screen.<ref name="GS-SI-Hall" /><ref name="GWR08-3" /><ref name="RG-41" /><ref name="NPR-VGMusic" /> The aliens attempt to destroy the player's cannon by firing projectiles. The laser cannon is partially protected by stationary defense [[bunker]]s which are gradually destroyed from the top by the aliens and, if the player fires when beneath one, the bottom gets destroyed.

As aliens are defeated, their movement and the music both speed up. Defeating all the aliens brings another wave which starts lower, a loop which can continue endlessly.<ref name="GS-SI-Hall" /><ref name="GWR08-3">{{cite book |editor=Craig Glenday |title=Guinness World Records Gamer's Edition 2008 |series=[[Guinness World Records]] |date=March 11, 2008 |publisher=Guinness |isbn=978-1-904994-21-3 |page=[https://archive.org/details/guinnessworldrec00guin_0/page/237 237] |chapter=Top 100 Arcade Games: Top 5 |chapter-url=https://archive.org/details/guinnessworldrec00guin_0 |url=https://archive.org/details/guinnessworldrec00guin_0/page/237 }}</ref><ref name="RG-41">{{Cite magazine|date=September 2007|title=The Definitive Space Invaders|url=https://archive.org/stream/retro_gamer/RetroGamer_041#page/24/mode/2up|magazine=[[Retro Gamer]]|issue=41|pages=24–33}}</ref><ref name="NPR-VGMusic">{{cite news |url=https://www.npr.org/templates/story/story.php?storyId=89612882 |title=Replay: the Evolution of Video Game Music |publisher=[[National Public Radio]] |work=[[All Things Considered]] |author=Seabrook, Andrea |date=April 12, 2008 |access-date=May 12, 2008 |author-link=Andrea Seabrook}}</ref> A special "mystery ship" will occasionally move across the top of the screen and award bonus points if destroyed.