Elemental Protections are displayed here, there are 5 different ones. When collected they will appear in the Inventory (see below for each element). The vertical bar is a timer and indicates how long the protection will last. In the game the ball will change its appearence too!
Fire Protection: Appears in the Inventory as . Appears in game as
Cold Protection: Appears in the Inventory as . Appears in game as
Acid Protection: Appears in the Inventory as . Appears in game as
Earth Protection: Appears in the Inventory as . Appears in game as
Electricity Protection: Appears in the Inventory as . Appears in game as
Strength, when collected will appear in the Inventory like this: and in-game the ball will display a trail like this: . The vertical bar displays the time remaining. Strength is good for smashing Damaged Walls. Having Strength will also prevent you from being crushed. As an example see Crushers.
Coloured Keys are used to open Gates, depending on which colour Key you have will depend on what colour Gate you can open. Each Key will open a single Gate of its colour.