Credit cards are a vital part of the way we both spend and manage our money. They allow us to quickly do financial transactions with a single swipe of plastic, greatly streamlining the process for everyone involved. Credit cards are also used for the system of building and retaining credit over time.
Lines of credit are essentially a contract between an individual and the lenders which they are taking out the line of credit from. The individual is able to pay a certain amount on the spot towards a purchase with the understanding that those funds will be paid back. Credit score is a representation of how able someone is to pay back their credit balances, and it stands to financial institutions as a way of measuring how reliable someone is.
Credit score is a matter of concern to most people, because it can affect any things in life. Being able to get loans approved and get housing leases signed or being able to purchase a car with low financing all rely on good credit scores to do easily. As such it is always a good idea to build up that score whenever possible.
A simple trick to use to both simplify your finances and to build credit alike is to only use one of two credit cards for purchases. Doing so will build your credit score if you focus on paying back the amounts you charge immediately. If you have more than two cards, completely pay off the balance on all but two and then focus on only using those. It is important to note that cancelling credit cards is not going to repair credit, so it is best to pay everything off and start fresh.
It is a fairly simple process, and it is one that gets good results!