Half-life (symbol t½) is the time required for a quantity (of substance) to reduce to half of its initial value. The term is commonly used in nuclear physics...

Half-Life 2 is a 2004 first-person shooter (FPS) game developed and published by Valve Corporation. It was published for Windows on Valve's digital distribution...

Half-Life is a 1998 first-person shooter game developed by Valve Corporation and published by Sierra Studios for Windows. It was Valve's debut product...

Half-Life is a series of first-person shooter (FPS) games created by Valve. The games combine shooting combat, puzzles and storytelling. The original...

Half-Life: Alyx is a 2020 virtual reality (VR) first-person shooter game developed and published by Valve. It was released for Windows and Linux, with...

This is a list of characters in the Half-Life video game series, which comprises Half-Life, Half-Life 2, Half-Life: Alyx, and their respective expansion...

Biological half-life (elimination half-life, pharmacological half-life) is the time taken for concentration of a biological substance (such as a medication)...

Half-life is a mathematical and scientific description of exponential or gradual decay. Half-life, half life or halflife may also refer to: Half-Life...

Half-Life 2: Episode Two is a 2007 first-person shooter game developed and published by Valve. Following Episode One (2006), it is the second of two shorter...

They are encountered throughout Half-Life 2, Half-Life 2: Episode One, and Half-Life 2: Episode Two, as well as Half-Life: Alyx, as hostile non-player characters...