Bleaching is a permanent removal of color from the hair and is done when a lightening of the hair is desired. It can also be done as a base step to remove all color from the hair so that it can be dyed another color.
Gloss is clear or base hair color that is applied to give hair shine. Treatments can be done between touch-ups to keep color vibrant or used every six to eight weeks in lieu of color.
Highlights refer to the creation of lighter-colored strands over a darker base. They can be subtle, natural-looking streaks or bold, chunky sections.
Layering is a choppy effect achieved with scissors or a razor.
Lowlights are darker strands woven into a lighter base. They can be used to tone down overly bright highlights or to blend away gray.
Partial high- (or low-) lights are usually applied to the crown and/or around the face (the rest of the hair remains the base color). The process saves time and money.
Permanent color is used when you want to go darker or lighter than your natural shade (also called a "depositing color"). When permanent color grows out, it leaves what hairdressers call a line of demarcation (meaning you can easily see the roots). It requires touch-up maintenance every four to six weeks and covers gray completely.
Razoring is a technique in which the stylist uses a blade to cut hair in wispy layers. This technique works best on straight hair and can be risky for frizzy hair, as poorly executed razoring can make the frizz worse.
Semi- or demi-permanent color coats the cuticle but doesn't penetrate the hair shaft. Color washes out gradually (usually in four to six weeks), so there's no demarcation line. It's good for blending gray, but won't cover it completely.
Tone describes what color the hair is. Warm tones have gold or red; cool tones don't. Red, copper and yellow are considered warm; ash brown and silvery blonde are considered cool.