"iShares Core MSCI World UCITS ETF" is an exchange-traded investment fund (ETF). It refers to the MSCI World Index. This index reflects the development of 1539 world wide stocks and is therefore very well diversified. The ETF replicates its index using physical replication with sampling, so it contains the most important securities of its reference index. The ETF's earnings (dividends) are automatically reinvested (accumulated). The fund company iShares claims a total expense ratio (TER) of 0.20% per year. The yearly average divergence from the index performance (Tracking Difference) since 2010 was 0.08% per year. Therefore, the ETF was less expensive than the TER suggests.
Comparing Tracking Difference, Total Expense Ratio and fund size
Every bubble represents an ETF. The further to the right it is, the higher (worse) is its tracking difference. The further up it is, the higher the total expense ratio specified by the fund company. The bubble's area represents the fund volume.