Investing glossary
Accumulating vs Distributing (Acc/Dist)
An accumulating share class (Acc) automatically reinvests dividends inside the fund; a distributing class (Dist) pays them out periodically in cash to the holder.
For long-term investing, the accumulating class is usually more efficient: it reinvests dividends with no transaction cost and no need for you to do it manually, maximizing the effect of compound interest.
The distributing class makes sense if you want to generate a periodic income (for example, to supplement your earnings), though in Spain receiving the dividend is taxed the same as any investment income at the time it is paid.