THE HAGUE, Netherlands — The Dutch inventor of the cassette tape, the medium of choice for millions of bedroom mixtapes, has died at the age of 94.

Philips, the company where he also helped develop the compact disc, confirmed that Lou Ottens died Saturday at age 94.

Ottens joined Philips in 1952 and was head of the Dutch company’s product development department when he began work on an alternative for existing tape recorders with their cumbersome large spools of tape.

His goal was simple: Make tapes and their players far more portable and easier to use.

Ottens completed his final product in 1962, which quickly revolutionized the audio industry. More than 100 billion cassettes were sold worldwide.