In one sentence, describe what the following article is about:

Many amps contain additional controls, such as ones for special effects like chorus, tremolo, delay, and reverb. Note, however, that you can often achieve a higher quality tone by using effects pedals to produce these effects. The most common effect to come equipped with an amp is reverb. The reverb effect produces a larger sound by simulating the sound wave bouncing off multiple surfaces. The reverb effect is subtle but powerful, and it can be used for a wide array of sounds. The world of guitar pedals (also called effects pedals, or stomp boxes) is nearly endless. The most versatile pedals are delay, distortion, and compression. Effect pedals range from about $30 to around $1,000. Effects pedals are typically powered by a 9V battery and must go in between your guitar and your amplifier in the chain. Plug your guitar into one end (the input) and your amp into the other end (the output), then use your foot to activate the effect while playing. Search online for a better idea of what effects and amplifier settings your favorite recordings are using. Classic/hard rock uses distortion/overdrive, flanger or phase, wah-wah, and delay. Blues guitar uses a variety of overdrives and amp simulator pedals. Country guitar utilizes tremolo and reverb. Shoegaze uses almost every pedal you can imagine but especially utilizes reverb, distortion, fuzz, delay, chorus, and tremolo. Once you get an understanding of your guitar needs you can invest in an amp that suits you. If you are playing out of a small practice amp, the best upgrade you should consider is a combo tube amp. For tube combo amps, you can usually get away with a single 12" speaker, but many prefer the louder cousin, two 12" speakers. Classic tube combo amps are made by Marshall, Fender, and Vox. You can also upgrade to a stack which consists of a guitar (or bass) head and a cabinet of two to four speakers.
Experiment with other controls on your guitar amp. Use additional pedals. Upgrade your amplifier.