On the Geo Meridian online travel guide (Geomerid.com) the "Islands of Spain" region includes the Islands of the Balearic archipelago in the Mediterranean sea, as well as the Canary Islands in the Atlantic ocean.
"Islands of Spain" - this is the Mallorca, Menorca, Ibiza and Formentera belonging to the archipelago of the Balearic Islands and the Islands of Tenerife, Grand Canary, Palma, Fuerteventura, La Gomera, El Hierro, included in the Canary Islands in the North Atlantic.
Both archipelagos are a great place for a beach holiday. In the Canary Islands swimming is possible all year round. Ibiza is a world center of youth dance music. In Mallorca and Menorca, the vacation leisure is more respectable.
In addition to swimming, there are excellent opportunities for trekking in the Canary Islands. In Tenerife, you must climb the Teide volcano, on Gran Canaria, see the Maspalomas dunes. All the Islands have many opportunities for trekking in mountainous areas among relict forests, gorges, and waterfalls.