Holy Tables

"Altar" has a meaning in the Orthodox Church that varies with context. It’s most common usage does not denote the table itself, but the area surrounding it; that is, the entire sanctuary. This includes both the area behind the iconostasis, and the soleas (the elevated projection in front of the Iconostasis), and the ambo. When one enters the sanctuary, one is said to be "going into the altar". The altar table itself may be referred to as either the Holy Table or the Throne (Prestól).
For Orthodox, altars (holy tables) are always free-standing, although in very small sanctuaries they might be placed flush against the back wall for reasons of space. Holy tables are typically about one meter high, and although they may be made of stone they are generally built out of wood. The exact dimensions may vary, but the holy table must be square in plan and in reasonable proportion to the size of the sanctuary. Holy table has five legs: one at each corner plus a central pillar for supporting the relics which are placed in it at its consecration. Over all is a plain linen cover (Srachítsa) bound to the altar with cords; this cover is never removed after the altar (holy table) is consecrated. The linen covering symbolizes the winding sheet in which the body of Christ was wrapped. Since the altar (holy table) is never seen uncovered thereafter, they tend to be constructed more with sturdiness than aesthetics in mind. Above this first cover of the holy table is a second ornamented cover (Indítia), often in a brocade of a color that may change with the liturgical season. This outer covering usually comes all the way to the floor and represents the glory of God's Throne.
Atop the altar (holy table) is the tabernacle (Kovtchég), a miniature shrine sometimes built in the form of a church, inside of which is a small ark containing the Reserved sacrament for use in communing the sick. Also kept on the altar (holy table) are the Gospel book and the antimension, a silken cloth imprinted with an icon of Christ being prepared for burial, which has a relic sewn into it and bears the signature of the bishop. The Divine Liturgy must be served on an antimension even if the altar (holy table) has been consecrated and contains relics. When not in use, the antimension is left in place wrapped in the eiliton, a cloth of plain silk, linen or cotton.
The altar (holy table) may only be touched by ordained men, no less than a Subdeacon, and nothing which is not itself consecrated or an object of veneration should be placed on it. Objects may also be placed on the altar (holy table) as part of the process for setting them aside for sacred use. For example, icons are usually blessed by laying them on the altar (holy table) for a period of time or for a certain number of Divine Liturgies before sprinkling them with holy water.
In place of the outer covering, some altars (holy tables) have a permanent solid cover which may be highly ornamented, richly carved, or even plated in precious metals. A smaller brocade cover is used on top of this if it is desired that the altar (holy table) decorations reflect the liturgical season.
The altar (holy table) is used as the place of offering in the celebration of the Eucharist, where bread and wine are offered to God the Father and the Holy Spirit is invoked to make his Son Jesus Christ present in the gifts. It is also the place where the presiding clergy stand at any service, even where no Eucharist is being celebrated and no offering is made but prayer.
Istok Church Supplies offers excellent altars (holy tables) of various sizes. Our holy tables can be richly decorated with hand-carving and even hand-carved icons of your choice. We welcome custom-orders and lecterns with custom-sizes.

(Partial source: Wikipedia.)