What is a penalty foul, and how is a penalty throw taken?

Penalty fouls (World Aquatics rules, Part Six, Article 11) include, inside your own 6 m area:

• any foul that prevents a likely goal;
• taking the ball under when tackled, if a goal was likely;
• pulling over or moving the goal;
• impeding an attacker from behind who is facing goal and shooting (the Referee waits to see the shot; if it scores, no penalty);
• a field player blocking with two hands, or playing the ball with a clenched fist.

Also: an excluded player deliberately interfering with play, improper entry (including without the correct cap), and the team not in possession calling a timeout.

Taking the penalty throw (Article 16):

• From any point on the 5 m line, by any player of the team, on the Referee's whistle and arm signal, in one uninterrupted movement straight at goal.
• Only the shooter and the goalkeeper may be inside the 6 m area; everyone else at least 3 m from the shooter. The goalkeeper must be on the goal line between the posts.
• If the goalkeeper moves forward before the whistle and the shot misses, the goalkeeper is excluded and the throw retaken.
• In the last minute of the match, the Head Coach may choose a free throw on or behind halfway, with a fresh 28 seconds, instead of the penalty.