Prior to decimalization in 1971, Britain used a system of pounds, shillings and pence introduced by King Henry II. The currency was denoted '£sd' or 'LSD' (L latin word libra; d coming from the latin word denarius).
One pound equalled 20 shillings and one shilling equalled twelve pennies. A guinea was 21 shillings. Two and six, abbreviated 2s 6d, was half a crown; a crown was five shillings. According to the National Archives, one pound seventeen in 1890 would have had the same purchasing power today as £112.29 (around $173). Two and six back in 1890 would be worth £7.49 today (around $11.60).