If you're looking to borrow a sum of money then the chances are that you'll look to take out a personal loan rather than any other type. The term personal loan is simply used to describe standard types of borrowing - i.e. a loan taken out by a consumer rather than a business for general purposes (but not for a mortgage which is obviously dealt with by a mortgage loan).
The majority of personal loans can be used for any purpose and the chances are that your lender won't even be hugely interested in what you want the money for. Their primary concern is checking that you'll be able to repay your loan! This situation can be different with specialist loans (which also fall under the banner of personal loans) such as home improvement loans and car loans, for example. These loans are expected to be used for their specified purpose - i.e. a major DIY project or a car purchase.
Apart from this fact the majority of personal loans work in much the same way. You apply for your loan, get your money and then spend it as you intended. You will then make a regular payment (usually on a monthly basis) to your lender to repay the money you borrowed for the period of time in your loans agreement. This payment will be made up of a sum of money that goes to pay off the original sum you borrowed plus a sum that goes towards paying off the interest you'll be charged. So, at the end of your loan term you'll have repaid your original borrowings and the interest attached to your particular loan.
One difference worth noting here is that between unsecured and secured personal loans. Unsecured loans are given to consumers without security (or to those that choose not to use available security to get a loan). These loans will generally have higher interest rates attached to them than secured loan options and you may be restricted in how much you can actually borrow here. Secured loans, on the other hand, will have lower interest rates and can be taken out for higher sums. The reason behind this is the fact that this kind of loan will use your property (usually your home) as a guarantee against your loan. So, if you default on your repayments your lender has a cast-iron guarantee that they will get their money back via the property you used as security.
If you aren't a home owner then you will generally be restricted to taking out unsecured loans here but, if you do own your own property, then you'll have to make a choice between a secured or unsecured loan. This really boils down to personal preference and how comfortable you are using your home as security in order to get a better deal. In the majority of cases this isn't an issue and most people will opt for secured loans to get the right kinds of rates and loan amounts for their purposes.
Do be careful to make sure that you understand both how personal loans work and how to get the best rates for the loans you take out before you sign up to anything. There are hundreds of sites on the Internet that can give you more detailed information or that can even help you apply for a loan - take a look online for personal loans in a UK search engine (such as msn.co.uk for example) before you start for some useful information.