This article is from the Hungarian FAQ, by Zoli Fekete fekete@bc.edu with numerous contributions by others.
If you are limited to the use of 7-bit ASCII, you have essentially the
following choices to deal with the accented characters:
5.2.1.0 No accent marks at all
Simple and sure-fire. In fact, the most common 'solution'.
5.2.1.1 The '~" coding (also called "marking notation" or "Babai-code")
[Sometimes nicknamed as _repu~lo"_.]
Here's a sample:
O~t hu"to"ha'zbo'l ke'rtu~nk szi'nhu'st
a'rvi'ztu"ro" tu~ko~rfu'ro'ge'p
O~t sze'p szu"zla'ny o"ru~lt i'ro't nyu'z
or, in the alternative ':" _repu:lo"_ format:
O:t hu"to"ha'zbo'l ke'rtu:nk szi'nhu'st
a'rvi'ztu"ro" tu:ko:rfu'ro'ge'p
O:t sze'p szu"zla'ny o"ru:lt i'ro't nyu'z
Quite readable, though a bit tricky to disambiguate mechanically:
remember, the " or : or ' may also serve as punctuation marks. (This
problem can be handled using Maxent's escaping capabilities, see 5.2.6.6.)
Warning! Don't get confused: in TeX (see 5.2.3.1) " denotes umlaut!
5.2.1.2 The 123 coding (also "numerical notation" or "Pro1sze1ky-code")
Here's the same text:
O2t hu3to3ha1zbo1l ke1rtu2nk szi1nhu1st
a1rvi1ztu3ro3 tu2ko2rfu1ro1ge1p
O2t sze1p szu3zla1ny o3ru2lt i1ro1t nyu1z
The only one that's both short and unambiguous, though it takes some
getting used to. 1 stands for the stroke, 2 for the short umlaut, 3 for
the 'Hungarian' or long umlaut (double acute). Very easily converted to
other formats. (Also can be ambiguous, though with much smaller
probability. E.g. U2, CO2, u21591@uicvm.uic.edu, etc.)
5.2.1.3 Telegraphic style. For example,
Oet huetoehaazbool keertuenk sziinhuust
aarviiztueroe tuekoerfuuroogeep
Oet szeep szuezlaany oeruelt iiroot nyuuz
Avoid it like the plague because
1. It's ambiguous. (Think of Goethe, Oetker, Eoersi, Csooori, poeen.)
2. Coding of o" & u" (o3 & u3) is not consistent:
u3 = ue (fallback to u2), uue, uee, ueue
3. Absolutely not a pleasure to read.
 
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