Aperture is a component of exposure control and refers to the size of the lens opening that lets light reach the sensor. The size of the opening can be adjusted and is described as an “f” number, as in f/2.0 or f/8.0. A wider aperture lets in more light, letting you use a faster shutter speed and/or a lower ISO; it also creates greater blur in front of and behind the object you’re focusing on, making it stand out more. A narrower aperture means you’ll have to use a slower shutter speed and higher ISO to get a sharp image. The trick is that a smaller f-number means a larger opening, so f/2.0 is a bigger opening than f/8.0.

Dynamic range refers to the span between bright and dark areas—highlights and shadows—that a camera can record simultaneously. A camera with high dynamic range can record details in both very bright and very dark areas of a scene. A camera with lower dynamic range will record details in highlights but miss those in the shadows, or vice versa depending upon how you bias the exposure.

DSLRs are the type of camera most people associate with “real” photography. These are the Canons and Nikons with interchangeable lenses and the telltale hump surrounding the optical viewfinder. The acronym stands for digital single lens reflex and refers to the mirror mechanism that lets you look through the viewfinder and then flips up to allow light to reach the sensor.

Image noise is the random collection of red, green, and blue specks obscuring details that you see in images shot in low-light conditions. It’s the result of a sensor having to greatly amplify its signal in order to render an image with very little light available.

ISO is a component of exposure control that indicates how much light your camera needs to record a well-exposed image. A range of ISO 100 to ISO 6,400 and higher is standard on most cameras—a far call from film days where ISOs higher than 400 were uncommon. At ISO 100, the camera needs a lot of light to record an image—which means you’ll need to use a longer shutter speed or wider aperture to get a well-exposed photo. At ISO 6,400 the camera needs only a small amount of light to record an image. The downside is that at higher ISO settings the camera produces higher levels of image noise.

Focal length describes the angle of view of a lens: how much of the scene it can take in. It is expressed in millimeters. The higher the number, the narrower the field of view. A 20mm lens is considered a wide focal length as it captures approximately an 84-degree angle of view. A 200mm lens, by comparison, offers a narrower, 10-degree angle of view, though with much greater magnification.

Mirrorless cameras differ from DSLRs in that they omit the system of mirrors and hinges required for an optical viewfinder, instead transmitting the image directly from the sensor to the screen. Because of this they can be much smaller and lighter while offering faster shooting rates. Entry-level mirrorless cameras drop the viewfinder altogether, requiring you to compose using the rear screen exclusively, but higher-end models come with electronic viewfinders so you can shoot with the camera held to your eye just like a DSLR.

Sensors are the digital equivalent of film. They record the light coming through the lens to make an image. They come in different physical sizes. All else being equal, a larger sensor can more efficiently record light than a smaller sensor, resulting in cleaner, more detailed images. A larger sensor can also give you blurrier backgrounds when shooting at wide apertures.

Superzooms are a breed of camera that pack an incredibly broad focal length range into a built-in zoom lens. Current models let you shoot wide-angle images at around 24 mm and super telephoto shots at 1400 mm, all without changing a lens. Although they are styled to resemble DSLRs, their small sensors yield image quality similar to a compact point-and-shoot camera.

Shutter speed is a component of exposure control that refers to the amount of time the shutter remains open. It is most often expressed in fractions of a second. Slower shutter speeds let more light reach the sensor, enabling you to get well-exposed images in low light. Faster shutter speeds allow less light to reach the sensor, but freeze the action of fast-moving subjects. A shutter speed of 1/60 second, for example, lets in more light than a shutter speed of 1/200 second. And while a 1/15 second shutter speed will let in even more light, it can also lead to motion blur in an image. If you use a short shutter speed, you may need a higher ISO or wider aperture to get a proper exposure.

Travel zooms are the pint-size siblings of superzooms. Their zoom ranges are limited to about half of what superzooms offer, but they are much smaller in size, easily fitting into a jacket pocket. With the same size sensors as their larger counterparts they deliver essentially identical image quality.

Viewfinders are what you look through when shooting with the camera held to your face. They come in two flavors. Traditional DSLRs use an optical viewfinder, a piece of high-quality glass that relies on mirrors to bounce incoming light from the lens. You see the scene as your lens renders it. Mirrorless cameras use an electronic viewfinder, providing a scene preview captured by the camera’s sensor. You see the scene as your sensor will ultimately record it.

Zoom lenses allow you to frame your composition at varying focal lengths without having to swap lenses. You simply rotate the lens barrel or slide a lever to get a closer or more distant view of your subject. Zoom lenses typically let in less light than fixed-focal-length lenses but offer the convenience of carrying less equipment in your camera bag. Lenses with a broad zoom range are often referred to by the multiplication factor between the widest and narrowest zoom settings. A 30x zoom lens offers a magnification at its telephoto end that is 30 times greater than at its widest end.