Unbranded 2 in. x 4 in. x 10 ft. Standard and Better Kiln-Dried Heat Treated Spruce-Pine-Fir Lumber

10 (ten) is the even natural number following 9 and preceding 11. Ten is the base of the decimal numeral system, the most common system of denoting numbers in both spoken and written language.

2 (two) is a number, numeral and digit. It is the natural number following 1 and preceding 3. It is the smallest and only even prime number. Because it forms the basis of a duality, it has religious and spiritual significance in many cultures.

4 (four) is a number, numeral and digit. It is the natural number following 3 and preceding 5. It is a square number, the smallest semiprime and composite number, and is considered unlucky in many East Asian cultures.

Better may refer to:

• "to better" as a verb, meaning to undergo betterment
• better, an alternate spelling of bettor, someone who bets (gambles)

Firs are evergreen coniferous trees belonging to the genus Abies () in the family Pinaceae. There are approximately 48–65 extant species, found on mountains throughout much of North and Central America, Europe, Asia, and North Africa. The genus is most closely related to Cedrus (cedar). The genus name is derived from the Latin "to rise" in reference to the height of its species. The common English name originates with the Old Norse, fyri, or the Old Danish, fyr.

They are large trees, reaching heights of 10–80 metres (33–262 feet) tall with trunk diameters of 0.5–4 m (1 ft 8 in – 13 ft 1 in) when mature. Firs can be distinguished from other members of the pine family by the way in which their needle-like leaves are attached singly to the branches with a base resembling a suction cup, and by their cones, which, like those of true cedars, stand upright on the branches like candles and disintegrate at maturity.

Identification of the different species is based on the size and arrangement of the leaves, the size and shape of the cones, and whether the bract scales of the cones are long and exserted, or short and hidden inside the cone.

In thermodynamics, heat is the thermal energy transferred between systems due to a temperature difference. In colloquial use, heat sometimes refers to thermal energy itself. Thermal energy is the kinetic energy of vibrating and colliding atoms in a substance.

An example of formal vs. informal usage may be obtained from the right-hand photo, in which the metal bar is "conducting heat" from its hot end to its cold end, but if the metal bar is considered a thermodynamic system, then the energy flowing within the metal bar is called internal energy, not heat. The hot metal bar is also transferring heat to its surroundings, a correct statement for both the strict and loose meanings of heat. Another example of informal usage is the term heat content, used despite the fact that physics defines heat as energy transfer. More accurately, it is thermal energy that is contained in the system or body, as it is stored in the microscopic degrees of freedom of the modes of vibration.

Heat is energy in transfer to or from a thermodynamic system by a mechanism that involves the microscopic atomic modes of motion or the corresponding macroscopic properties. This descriptive characterization excludes the transfers of energy by thermodynamic work or mass transfer. Defined quantitatively, the heat involved in a process is the difference in internal energy between the final and initial states of a system, and subtracting the work done in the process. This is the formulation of the first law of thermodynamics.

Calorimetry is measurement of quantity of energy transferred as heat by its effect on the states of interacting bodies, for example, by the amount of ice melted or by change in temperature of a body.

In the International System of Units (SI), the unit of measurement for heat, as a form of energy, is the joule (J).

A kiln is a thermally insulated chamber, a type of oven, that produces temperatures sufficient to complete some process, such as hardening, drying, or chemical changes. Kilns have been used for millennia to turn objects made from clay into pottery, tiles and bricks. Various industries use rotary kilns for pyroprocessing (to calcinate ores, such as limestone to lime for cement) and to transform many other materials.

Lumber is wood that has been processed into uniform and useful sizes (dimensional lumber), including beams and planks or boards. Lumber is mainly used for construction framing, as well as finishing (floors, wall panels, window frames). Lumber has many uses beyond home building. Lumber is referred to as timber in the United Kingdom, Europe, Australia, and New Zealand, while in other parts of the world (mainly the United States and Canada) the term timber refers specifically to unprocessed wood fiber, such as cut logs or standing trees that have yet to be cut.

Lumber may be supplied either rough-sawn, or surfaced on one or more of its faces. Rough lumber is the raw material for furniture-making, and manufacture of other items requiring cutting and shaping. It is available in many species, including hardwoods and softwoods, such as white pine and red pine, because of their low cost.

Finished lumber is supplied in standard sizes, mostly for the construction industry – primarily softwood, from coniferous species, including pine, fir and spruce (collectively spruce-pine-fir), cedar, and hemlock, but also some hardwood, for high-grade flooring. It is more commonly made from softwood than hardwoods, and 80% of lumber comes from softwood.

A pine is any conifer tree or shrub in the genus Pinus () of the family Pinaceae. Pinus is the sole genus in the subfamily Pinoideae.

World Flora Online, created by the Royal Botanic Gardens, Kew, and Missouri Botanical Garden, accepts 187 species names of pines as current, together with more synonyms, making it the largest family among the conifers. The American Conifer Society (ACS) and the Royal Horticultural Society accept 121 species. Pines are widely distributed in the Northern Hemisphere; they occupy large areas of boreal forest, but are found in many habitats, including the Mediterranean Basin.

The lumber from pine trees is called "pine"; it is one of the more extensively used types of lumber. There are currently 818 named cultivars (or trinomials) recognized by the ACS. It is a well-known type of Christmas tree.

A spruce is a tree of the genus Picea ( py-SEE-ə), a genus of about 40 species of coniferous evergreen trees in the family Pinaceae, found in the northern temperate and boreal (taiga) regions of the Earth. Picea is the sole genus in the subfamily Piceoideae. Spruces are large trees, from about 20 to 60 m (about 60–200 ft) tall when mature, and have whorled branches and conical form.

Spruces can be distinguished from other genera of the family Pinaceae by their needles (leaves), which are four-sided and attached singly to small persistent peg-like structures (pulvini or sterigmata) on the branches, and by their cones (without any protruding bracts), which hang downwards after they are pollinated. The needles are shed when 4–10 years old, leaving the branches rough with the retained pegs. In other similar genera, the branches are fairly smooth.

Spruce are used as food plants by the larvae of some Lepidoptera (moth and butterfly) species, such as the eastern spruce budworm. They are also used by the larvae of gall adelgids (Adelges species).

In the mountains of western Sweden, scientists have found a Norway spruce, nicknamed Old Tjikko, which by reproducing through layering, has reached an age of 9,550 years and is claimed to be the world's oldest known living tree.

Unbranded is a 2015 American documentary film directed by Phillip Baribeau. It follows four Texas A&M graduates setting out to ride sixteen mustangs from Mexico to Canada in order to raise awareness about issues surrounding wild horses and their management by the United States Bureau of Land Management.

X, or x, is the twenty-fourth letter of the Latin alphabet, used in the modern English alphabet, the alphabets of other western European languages and others worldwide. Its name in English is ex (pronounced ), plural exes.