In the UK, lenders will use one of the three primary credit-referencing agencies. Each report will be split into three categories:
Financial accounts - all of your credit accounts, from mortgages to mobile phone contracts.
Public information - court judgements against you, such as CCJs.
Credit checking history - how many checks have been run against your file.
Your reports include linked addresses you have lived at before, whether you are registered on the electoral roll, and if you have any previous names.