An Old English poem such as Beowulf is very different from modern poetry. Anglo-Saxon poets typically used alliterative verse, a form of verse in which the first half of the line (the a-verse) is linked to the second half (the b-verse) through similarity in initial sound. In addition, the two halves are divided by a caesura: "Oft Scyld Scefing \\ sceaþena þreatum" (l. 4). This verse form maps stressed and unstressed syllables onto abstract entities known as metrical positions. There is no fixed number of beats per line: the first one cited has three (Oft SCYLD SCEFING, with ictus on the suffix -ING) whereas the second has two (SCEAþena ÞREATum).
The poet has a choice of epithets or formulae to use in order to fulfil the alliteration. When speaking or reading Old English poetry, it is important to remember for alliterative purposes that many of the letters are not pronounced in the same way as in modern English. The letter ⟨h⟩, for example, is always pronounced (Hroðgar: [ˈhroðgar]), and the digraph ⟨cg⟩ is pronounced [dʒ], as in the word edge. Both ⟨f⟩ and ⟨s⟩ vary in pronunciation depending on their phonetic environment. Between vowels or voiced consonants, they are voiced, sounding like modern ⟨v⟩ and ⟨z⟩, respectively. Otherwise they are unvoiced, like modern ⟨f⟩ in fat and ⟨s⟩ in sat. Some letters which are no longer found in modern English, such as thorn, ⟨þ⟩, and eth, ⟨ð⟩ – representing both pronunciations of modern English ⟨th⟩, as /θ/ in thing and /ð/ this – are used extensively both in the original manuscript and in modern English editions. The voicing of these characters echoes that of ⟨f⟩ and ⟨s⟩. Both are voiced (as in this) between other voiced sounds: oðer, laþleas, suþern. Otherwise they are unvoiced (as in thing): þunor, suð, soþfæst.
Kennings are also a significant technique in Beowulf. They are evocative poetic descriptions of everyday things, often created to fill the alliterative requirements of the metre. For example, a poet might call the sea the "swan-road" or the "whale-road"; a king might be called a "ring-giver." There are many kennings in Beowulf, and the device is typical of much of classic poetry in Old English, which is heavily formulaic. The poem also makes extensive use of elided metaphors.
J. R. R. Tolkien argued in Beowulf: The Monsters and the Critics that the poem is not an epic, and while no conventional term exactly fits, the nearest would be elegy.