Hood typically carried 16-18 boats. On the diagram you've linked, where two or more boats are named, the smaller one is stored inside the larger. She had this many boats because she needed them; boats were used for mooring the ship to buoys, carrying men ashore, rescuing men overboard and many more tasks. Most large warships carried a similar number of boats. However, during WWII, the number of boats carried dropped. This freed up space and topweight for new anti-aircraft guns. The boats removed from the ships were concentrated at the RN's main bases, forming a boat pool that could be used by any visiting ship.

Probably the most important role of the boats was in carrying men ashore. Many of the RN's bases did not have room for multiple large warships to come alongside a quay or jetty, nor did many of the foreign ports the RN visited. Instead, the ships had to moor out in the harbour. At these bases, boats were needed to take men to the shore for liberty or for duties ashore, as well as carrying post and the like. The two 'picket boats' (labelled as Steam Pinnace on the diagram) were the main boats used for harbour duties like this, supplemented by other boats as needed. If Hood was carrying an admiral (as she usually did), he would have his own boat, the 'Admiral's Barge', for his own use. The boats were also useful for landing men in more warlike contexts. Hood carried a marine detachment of about 150 men; combined with armed sailors, she could deploy a quite formidable landing force should the situation call for it. This force was landed by the ship's boats. While this was never done in anger, it was a frequent part of interwar exercises. During the Spanish Civil War, Hood's boats were used to land supplies of food for the British consulate in Barcelona, as well as evacuating civilians from the region.

The boats were also necessary for the ship's general work. Hood frequently had to moor to buoys in harbours around the world. This operation required a single boat, which would carry the mooring cable to the buoy and attach it to the buoy. The boat used for this was typically one of the cutters. The cutters were also used as 'seaboats'. The seaboat was the ship's main lifeboats, used to rescue men who had fallen overboard and the like. They were also used to carry boarding parties to investigate suspicious ships, or to render assistance to other ships in danger. The boats could be used as lifeboats for the ship's crew, if the ship sank. However, they could not carry the full crew; a 1920s calculation indicated that Hood's boats could only carry 759 men of her peacetime crew of ~1150 (her wartime crew rose to over 1400). The remainder had to use liferafts, or boats from other ships.

The ship's boats had an important role in training. Each boat was commanded by a midshipman. This gave these junior officers a significant experience of command. It taught them how to give orders and ensure they were carried out. It also taught them how to relate to the men they commanded, how to look after them. The experience was viewed as a vital part of an officer's training as a seaman. The boats were also useful for exercises. Hood had four torpedo tubes, two on each side. In practices, these fired torpedoes with an inert teak warhead, set to float at the end of their run. They were also fitted with a calcium flare, to mark its location. One of Hood's smaller boats would be detailed to recover them; a torpedo, costing ~£2000 (in 1921 pounds) was too expensive to lose. Sometimes, the boats would represent the enemy, representing attacks by motor torpedo boats on a fleet in harbour.

Finally, boats played an important part in recreation. Beyond their use in taking liberty men ashore, they were commonly used for sailing and rowing ('pulling'). These were some of the most hotly contested sports within the fleet. There were multiple highly prestigious regattas which took place throughout the year. Hood was a common winner of these, winning the Home Fleet regatta five times. This level of athletic prowess required a considerable effort. Every one of Hood's boats competed, and winning meant serious, freqeunt practice. Regattas were also common on port visits, with competitions between the RN and other navies. For example, in 1922, Hood competed with the Brazilian and US Navies in a rowing regatta during a port visit to Rio.