The health meter, also commonly known as the health bar or life meter, is a recurring gameplay mechanic within Mario and its related franchises. It is an onscreen indicator of how much health the player character currently has left. It is usually a part of the HUD, and is usually found on the top part of the screen. The health meter varies on how many sections it has between its appearances. Some games do not display the health meter if the player character is at full health.
The Legend of Zelda franchise
The first Mario-related game to have a health meter is The Legend of Zelda, in which Link's health is represented by hearts. This was also made the case in subsequent The Legend of Zelda series titles as well as the Hyrule Warriors series.
In the Mario franchise itself, Super Mario Bros. 2, or Doki Doki Panic, if counting the original release, is the first title to have a health meter. Most 2D Super Mario series titles do not have a health meter because Mario's health is measured by power-ups, such as his Super form indicating that if he takes damage from an enemy or an obstacle, he turns into his Small form, and by taking damage again, he loses an extra life.
In the spinoff Yoshi franchise, a health meter first appears in Yoshi's Story. It is a specific type of health meter, known as the Smile Meter, and it has appeared in a few subsequent Yoshi platforming series titles. The Yoshi's Island series does not feature a health meter.
Super Smash Bros. series
In the Super Smash Bros. series, a damage meter is a key gameplay mechanic, and it appears in every installment starting with Super Smash Bros.. The damage meter differs depending on some of the VS. Mode battles, but it keeps track of how much damage the fighters take. In regular battles, each player's health is represented by an incremental damage percentage meter. In Stamina battles, it is represented by a decreasing HP, similar to more traditional health meters.
Donkey Kong franchise
In the Donkey Kong franchise, a health meter did not debut until the release of Donkey Kong Country Returns, in which each Kong is represented by two hearts. This is because in earlier Donkey Kong Country series titles, if a Kong takes damage, the player loses that Kong.