Types of Legal mortgage

There are essentially two types of legal mortgage.

Mortgage by demise
In a mortgage by demise, the creditor becomes the owner of the mortgaged property until the loan is repaid in full (known as "redemption"). This kind of mortgage takes the form of a conveyance of the property to the creditor, with a condition that the property will be returned on redemption.
This is an older form of legal mortgage and is less common than a mortgage by legal charge. It is no longer available in the UK, by virtue of the Land Registration Act 2002.

Mortgage by legal charge
In a mortgage by legal charge, the debtor remains the legal owner of the property, but the creditor gains sufficient rights over it to enable them to enforce their security, such as a right to take possession of the property or sell it.
To protect the lender, a mortgage by legal charge is usually recorded in a public register. Since mortgage debt is often the largest debt owed by the debtor, banks and other mortgage lenders run title searches of the real property to make certain that there are no mortgages already registered on the debtor's property which might have higher priority. Tax liens, in some cases, will come ahead of mortgages. For this reason, if a borrower has delinquent property taxes, the bank will often pay them to prevent the lienholder from foreclosing and wiping out the mortgage.
This type of mortgage is common in the United States and, since 1925, it has been the usual form of mortgage in England and Wales (it is now the only form - see above).
In Scotland, the mortgage by legal charge is also known as standard security.