So what is the difference between Mortgages and Secured Loans?
In general, there is no difference. A mortgage is a secured loan - it is a loan that gives you a cheaper interest rate because it knows you are very likely to make the payments and that you are low risk. If someone refers to a mortgage as a secured loan they are not incorrect because mortgages are secured loans.
However, there is a terminology difference that is largely semantics but can make a difference when you are taking a loan. A mortgage is the first loan taken to purchase your home. It is a secured loan, yes, but your first mortgage has different rights than if you take additional secured loans off your home (which are sometimes known as "second mortgages).
First of all the first mortgage you get is your primary mortgage. Even if you take out a secured loan against your home, if you default on both loans your mortgage is the one that gets the right to repossess your house and your secured loan only gets its secondary right (meaning that if you default on the secured loan but not the mortgage, the secured loan can repossess your house). These extra rights for the mortgage means extra risk for the secured loan, because the secured loan is not quite as "Secured" as it sounds.
Some Final Small Differences
Also, a mortgage may be a secured loan, but a secured loan is not necessarily a mortgage. You can get a secured loan using any type of valuable collateral. A car loan is also a secured loan and a loan against jewelry is a secured loan. Mortgages only refer to homes, and in general they only refer to the first loan you get to pay for a home, because the second secured loan is called either a "Secured loan" or a "Second Mortgage."
Otherwise they are referring to the same thing. So when you see secured loan information and it appears they are talking about mortgages, rather than the traditional type of secured loan, they are technically the same thing.