La talla lítica se refiere a troceado intencional de la piedra, por medio de la percusión (directa o indirecta) o de la presión, a diferencia de la técnica, posterior en el tiempo, del pulimentado. La materia prima se esculpe y se le da forma, aprovechando la fractura concoidea, con el objeto de fabricar útiles nucleares, o para extraer lascas. Éstas podían ser usadas en bruto, o servir de soporte para herramientas, retocándolas después de su extracción. El término talla no tiene implicaciones ni connotativas ni denotativas acerca de su finalidad, lo único que indica es que es intencional y que busca la elaboración de un artefacto lítico. Dentro de la talla, sin embargo, podemos usar términos más restrictivos (la hechura, el lascado y el retoque) que se explican más adelante. La talla lítica es el proceso de fabricación de manufacturas más conocido de la Edad de piedra, pero siguió siendo muy importante durante la Edad de los Metales, e incluso sigue practicándose en tiempos históricos. Los objetos de piedra tallada intencionalmente por los humanos se diferencian de las roturas naturales o accidentales, gracias a que son localizados en contextos arqueológicos bien definidos, y a que los golpes de la talla dejan negativos de lascado que siguen cierta tendencia, cierto orden imposible de atribuir a la naturaleza. El repertorio de gestos de talla organizada se va conociendo cada vez mejor y permite establecer diagnósticos cada vez más seguros, así como un repertorio de pautas morfológicas, técnicas y funcionales que son las que permiten establecer la tipología lítica, es decir, la clasificación, análisis y comparación de los artefactos de piedra tallada. La talla lítica no es, en cualquier caso, más que una de las fases de la vida de un artefacto lítico o, por expresarlo en términos científicos más precisos, solo es una porción relativamente corta de la cadena operativa. Ésta nace con la necesidad o la idea que estimula al ser humano a iniciar su actividad productiva, sigue con la búsqueda de la materia prima pétrea, su transformación mediante la talla, hasta conseguir el, o los útiles necesarios. Después está su utilización, incluyendo varias fases de mantenimiento de la funcionalidad por medio de reafilados y, cuando la herramienta es ya inservible, su abandono. A veces, la pieza es reciclada y vuelve a entrar, por un tiempo, en la cadena operativa, pero indefectiblemente será desahuciada y olvidada hasta que, tal vez, con mucha suerte, algún arqueólogo la recoja para su estudio.

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Lithic reduction involves the use of a hard hammer percussor, such as a hammerstone, a soft hammer fabricator (made of wood, bone or antler), or a wood or antler punch to detach lithic flakes from a lump of tool stone called a lithic core (also known as the "objective piece"). As flakes are detached in sequence, the original mass of stone is reduced; hence the term for this process. Lithic reduction may be performed in order to obtain sharp flakes, on which a variety of tools can be made, or to rough out a blank for later refinement into a projectile point, knife, or other object. Flakes of regular size that are at least twice as long as they are broad are called blades. Lithic tools produced this way may be bifacial (exhibiting flaking on both sides) or unifacial (exhibiting flaking on one side only). Cryptocrystalline or amorphous stone such as chert, flint, obsidian, and chalcedony, as well as other fine-grained stone material, such as rhyolite, felsite, and quartzite, were used as a source material for producing stone tools. As these materials lack natural planes of separation, conchoidal fractures occur when they are struck with sufficient force. The propagation of force through the material takes the form of a Hertzian cone that originates from the point of impact and results in the separation of material from the objective piece, usually in the form of a partial cone, commonly known as a lithic flake. This process is predictable, and allows the flintknapper to control and direct the application of force so as to shape the material being worked. Controlled experiments may be performed using glass cores and consistent applied force in order to determine how varying factors affect core reduction. By understanding the complex processes of lithic reduction, archaeologists recognize that the pattern and amount of reduction contribute tremendous effect to lithic assemblage compositions. One of the measurements is the geometric index of reduction. There are two elements in this index: 't' and 'T'. The 'T' is the 'height' of maximum blank thickness and the 't' is the height of retouched scar from the ventral surface. The ratio between t and T is the geometric index of reduction. In theory this ratio shall range between 0 and 1. The bigger the number is the larger amount of lost weight from lithic flake. By using a logarithmic scale, a linear relationship between the geometric index and the percentage of original flake weight lost through retouch is confirmed. In choosing a reduction index, it is important to understand the strengths and weaknesses of each method, and how they fit to the intended research question, as different indices provide different levels of information. For example, Kuhn's geometric index of unifacial reduction (GIUR), which describes the ratio of scar height relative to the flake thickness, is highly influenced by the morphology of the flake blank which limits the applicability of this reduction index. It has been shown that stages in the lithic reduction sequence may be misleading and that a better way to assess the data is by looking at it as a continuum. The assumptions that archaeologists sometimes make regarding the reduction sequence based on the placement of a flake into a stage can be unfounded. For example, a significant amount of cortex can be present on a flake taken off near the very end of the reduction sequence. Removed flakes exhibit features characteristic of conchoidal fracturing, including striking platforms, bulbs of force, and occasionally eraillures (small secondary flakes detached from the flake's bulb of force). Flakes are often quite sharp, with distal edges only a few molecules thick when they have a feather termination. These flakes can be used directly as tools or modified into other utilitarian implements, such as spokeshaves and scrapers.

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