Before the outbreak of war, the Kaiser had made no secret of his desire to supplant Britannia as ruler of the waves and had invested a great deal in building up the German navy. See Dreadnought and Anglo-German naval arms race.
As an island country, Britain had historically always given great importance to its naval strength and valued its maritime supremacy.
To understand the Battle of Jutland, you need to know about the Blockade of Germany.
The blockade was pretty effective and so by May 1916 German naval command decided to try to inflict a serious blow on the British. See this account of the battle: Battle of Jutland.
Both sides claimed victory. The British suffered great loss of life, but for the rest of the war they were able to maintain the blockade and were not again seriously challenged by the German navy.Both sides claimed victory. The British lost more ships and twice as many sailors but succeeded in containing the German fleet. However, the British press criticised the Grand Fleet's failure to force a decisive outcome while Scheer's plan of destroying a substantial portion of the British fleet also failed. Finally, the British strategy to prevent Germany access to both Great Britain and the Atlantic did succeed which was the British long term goal. The Germans' "fleet in being" continued to pose a threat, requiring the British to keep their battleships concentrated in the North Sea, but the battle confirmed the German policy of avoiding all fleet-to-fleet contact. At the end of the year, after further unsuccessful attempts to reduce the Royal Navy's numerical advantage, the German Navy accepted that their surface ships had been successfully contained, subsequently turning its efforts and resources to unrestricted submarine warfare and the destruction of Allied and neutral shipping which by April 1917 triggered the United States of America's declaration of war on Germany.