You may have had this experience before: you look at a word, and think to yourself “That can’t be how it’s spelled… is that right?” … that first R in February just looks wrong, sometimes. You may also have found yourself at some point asking your English teacher why something is spelled the way it is. If you got more than a response of “Because it just is.”– you’re lucky! Few people study orthography (the part of language concerned with letters and spelling), and fewer stills its history. However, we actually can find a lot of information about why words are spelled the way they are, by learning about their etymology—the chronology of a word’s form and meaning from its earliest (recorded) sources to current usage and spelling. It is a bit of a myth that English spelling is so strange because it is entirely random and arbitrary
The English language is a famous borrower—with roughly 200,000 words in the English lexicon (vocabulary), tens of thousands of words have been borrowed from several other languages, in particular Latin and French, which together account for half or more of the sources of modern English words. Other words are derived from Germanic languages, Greek, Spanish, Italian, Arabic, Chinese, you name it—and as a consequence of this global borrowing, there is added diversity in the spellings of words. This is because English orthography is relatively opaque: the relationship between letters and the sounds they represent is far from a perfect 1-to-1 mapping. For example, ‘K’ usually represents the phonological form (sound) /k/, a hard sound like in “kid”—but sometimes it’s read as /n/ like in “knife”, where it is part of the digraph (two letters that represent a single unit) ‘KN’. The letter ‘C’ is especially challenging—it can also represent the hard /k/, like the second ‘C’ in “circle”, but also the sound /s/, like the first ‘C’ in that same word! Or it can be part of the digraph ‘CH’, which can represent the sound /tS/ like in “choose”. And of course, there are those dreaded silent letters, like the ‘C’ in “indict”!
So, why is English spelling so irregular? It turns out that there is some method to the madness, which is beautifully described by D.W. Cummings in his book “American English Spelling”. The gist of it is, our spelling system as a whole is the result of a balance between competing ideas of what a words spelling should convey. You might think that the letters we use to spell a word should just tell us its sound—this is the phonetic demand. What would happen if we took this demand to the extreme, however? Should we spell the same word differently depending on the accent of the speaker—should “car” be spelled k-a-r for some of us but k-a-h for Bostonians? Should we spell homophones, words that have the same sound but different meanings, the same way—“two to many to count” becomes “too too many too count”? And how about the ‘S’ at the end of “cats” versus “dogs”—the first is pronounced as an /s/ but the second as a /z/ (say it aloud to yourself if you don’t believe me!)—should we write “It’s raining kats and dogz!”? A purely phonetic system, then, becomes problematic, because some sounds have multiple meanings, and because some words have multiple acceptable pronounciations.
Much of the oddness in our word spellings, then, comes from a desire to use the orthography to disambiguate meaning, or to give clues to the origin of the word (and, ideally, its definition). We want to spell “dogs” with an ‘S’ so that we consistently write our plural marker with that letter. For another example, although the ‘G’ in “sign” is not pronounced, it allows us to see its relationship with other words like “signature” (and not confuse it with “sine”!).
Admittedly, the system could be improved. Some of the oddities are no longer practically useful. Unless you speak Latin, the silent ‘C’ in “indict” or the ‘B’ in “debt” are not very helpful (they’re re-introduced nods to the original Latin “indictare” and “debitum”). In fact, several letters of the alphabet could probably be done away with entirely, if we were only willing to let go holdovers from their sources (for example, ‘X’ could be replaced with “ks” or “gz”). Ultimately, changes in spelling, like changes in language in general, occur continuously and naturally through social processes—what’s “here” today may be “gon tomarow”.
http://www.dwcummings.com “A Site for spellers, teachers of spelling and reading, and students of English words”
https://www.etymonline.com Online etymological dictionary
Further reading: Chapter 1 in Cummings, D.W. (1988). American English Spelling. JHU Press: Baltimore.