When all is said and done, the only way to know for sure what a certain set of strings will sound like on your guitar is to take them for a spin. For that reason, it's not a bad idea to try out a few different ones that interest you to see which ones you like best - then you can stock up! However you like to approach your string shopping, the amazing selection you'll find here is sure to satisfy.
Play the A Major. This is another "big chord," sonically. There are several ways to play this. You can use one finger across the 2nd fret of the B, G, and D strings (playing C#, A, and E, respectively), or any other combination of fingers. For this example, we'll use the 4th finger on the B string, 3rd finger on the G string, and 2nd finger on the D string.
Unlike many string instruments which use a bow to create a sound, guitars are played by plucking or strumming the strings on the instrument, which vibrate to create a sound. Chords are played when the guitarist holds their fingers down on more than one individual string to change its length, which in turn changes the frequency of the vibration created - in other words, it creates a different note. Performers often use guitar tabs, rather than sheet music, when learning music: this acts as a kind of 'map' to teach guitarists where to put their fingers on the strings.