I've just been sorting stamps by Scott numbers and what
a pain trying to find some of them in the catalog, primarily
because they don't illustrate half of them.
Like Czechoslovakia, before that country started incorporating dates
in the design where Scott lists similar types only by their
illustration number.
Locating the date somewhere on the design is the only way to find from any in the annual Art series
or The Treasures of the Prague Castle sets for example.
And how about this one from Egypt.

No date or inscription which would help. There is no more
AR Egypt only Egypt so its after 1976.
But at that time the values were still indicated by
m(illiemes) wheres this has a
p(iasters) which makes
it after 1982.
Still can't find it.
Finally found it. AIRMAIL Scott C178.
Maybe "airmail" is written in Arabic somewhere on the stamp but I can only
read Latin script and sometimes have problems with that.
I realize that with the enormous numbers of stamps being
issued every year it's a matter of space & weight.
Bu there has to be a better way.