Obviously, English typically has has the word order subject-verb[-(direct) object] (or SVO, for short). This can be altered in specific situations due to WH-movement (e.g. OSV in "What would you like?") and other structures, but SVO is the normal word order.
However, this isn't the only possible word order. Basic combination math tells us that there are six possible orders: SVO, SOV (e.g. Japanese, Korean, Latin, and Proto-Indo-European), VSO (e.g. Hebrew, Trique, and Caia), VOS, OSV, OVS; these are, however, not all equally likely.
Two rules have been developed which govern the prominence of different word orders. First, there's a tendency for the subject to precede the (direct) object. This is known as subject salience. There have been various theories on the exact reason for this; the general idea is that it's more natural for the subject to precede the object because they subject is typically the source of an action, and thus precedes the object in both cause and effect and chronological order.
The other is that there is a tendency for the object to sit next to the verb (on either side). Linguistics thus far has developed the notion that the object and the verb logically form a structure called the predicate, which stands apart from the subject (i.e. a clause is typically defined as a subject + a predicate). I haven't investigated the full depth of why this has been decided, so I couldn't really give more detail than that (though it's noteworthy that this idea is consistent with my hypothesis that language began as commands - the command forms the predicate, and the subject was added in later).
Thus, we have four classes of word order: those that meet both conditions, those that meet one or the other, and those that meet neither. In agreement with theory, SVO and SOV are by far the most common among languages, at 42% and 45%, respectively. On the distant second tier is VSO, which places the subject between verb and object, occurring with 9% frequency. On the again distant third tier are VOS, and OVS, each placing the object before the subject; these occur with 3% and 1% frequency, respectively. At the bottom is OSV, which violates both rules, and was not seen in any language in this survey of 402 languages.
Clearly the subject salience rule dominates in significance, as orders where object precedes subject are very rare (3% or less); although it's also true that languages where the object is not next to the verb are uncommon (9% or less).