Power Star

Power Stars are the main collectible of Super Mario 64. They are a reoccuring item in several other Mario games, either being a power-up making Mario invincible, or a collectible. They are obtained by finding them throughout the courses and castle, usually through the star select screen, where you select scenarios AKA missions, with specific situations to obtain a star. When a star is collected and seen again, it will be translucent and a shade of gray and blue.

Locations
In every of the 15 main worlds, there are 6 Power Stars (7 in the remake) in each world.

They are generally claimed via the following kinds of missions:

Defeating a boss character in a Boss Fight (one)

Gathering all the 8 Red Coins in of the current world (one)

Various tests of skill (one or two)

Finding hidden Stars by exploring the level (one or two)

By collecting all the 100 Coins in a level (one)

If the player has collected all 100 Painting Stars, they can go back and collect 100 plus Coins in each level to gain another Star, equaling 115.

Five more Power Stars can be gained as follows: Two are in The Princess's Secret Slide, one in The Secret Aquarium, and two from a castle Toad. In total, the full bar will equal 120 Stars. In Super Mario 64 DS, thirty extra Stars have been added, increasing the number of collectible Power Stars to 150. Also in the remake, an extra 7th Star has been added in each world

Silver Stars
Silver Stars are collectibles in Super Mario 64 DS, taking the appearance of gray Power Stars. However, if the player is damaged, they will drop a Silver Star that will have to be recollected. Silver Stars have been reported to appear in personalized copies of Super Mario 64. They usually function similarly to red coins, and are commonly a reskin of the spinning beta star, though have been reported to be reskins of regular stars.