An Exchange Traded Fund (ETF) is a form of Collective Investment Scheme and contains a pool of investments (‘the scheme property’) derived from the contributions of investors.
STSM101060 - Introduction to Collective Investment Schemes: Exchange Traded Fund
The taxation of ETF's is determined by the the asset class. Bonds are subject to Income Tax, with equities and commodities being subject to dividend tax. All three are subject to Capital Gains Tax.