Calm yourself. Help is here!
Once upon a time long ago, the мягкий знак - "soft sign" (henceforth, simply ь) and the твердый знак - "hard sign" (henceforth ъ) were both short vowels, pronounced something like the /i/ in "pit" and the /u/ in "put." What is more, long ago Russian syllables tended toward something called "pleophony," meaning, they tended to end in vowels, which meant that all words ended in vowels.
You still see this in feminine and neuter nouns which end in а/я or о/е respectively:
fem: экономика, тетя, симфония.
neut: электричество, море, влияние.
The point being that masculine nouns also once ended in vowels - the short vowels ь and ъ:
masc. учитель, профессоръ.
The trouble was that in time ь and ъ lost their vocalic quality, i.e., they stopped being pronounced as vowels and no longer formed syllables.
The ь and ъ continued to be written in all Russian texts, but now they were used as "phonetic markers" - the ь indicated that the preceding consonant was "soft" (palatalized), while the ъ indicated that the preceding consonant was "hard" (non-palatalized).
"So why was профессоръ changed to профессор?"
"The damn Commies!"
Yes, after the 1917 Revolution, some Bolshevik decided that the ъ was "redundant," meaning that since neither the ь nor the ъ were vowels and since the ь marked palatalization, the ъ could just as well be "purged" at the end of words.
One of the RLM's old emigre professors claimed the Bolsheviks did this to save ink and paper! He might have had a point. Even prepositions like в and к were written въ and къ. In one long-winded edition of Pravda that's a lot of ink and paper!
Anyway, the ъ remained only in words where it served a "phonetic function," in words like объект, подъем and съесть, where it indicates that the preceding consonant is "hard" (non-palatalized) and that the "soft vowel" which follows has a jot (a /j/ sound) in front of it.
In other words, phonetically
объект is /object/ Were the ъ not there, the "soft vowels" would indicate that the preceding vowel is palatalized and the three noted forms would be pronounced /ob'ekt/, /pod'om/ and /s'est'/ - with "soft consonants" and no jot. Consequently, съесть (perf.) ~ "to eat," would sound exactly like сесть (perf.) ~ "to sit down." Both would be pronounced /s'est'/.* * *
подъем is /podjom/
съесть is /sjest'/.
Back to those damn Commies. After the new Orthographic Reforms Decree was issued (10 October 1918), some reactionary Russians at home and abroad refused to drop their final ъ! One of the leading orthographic dissidents in the USSR was the highly respected cultural historian and philologist, Dmitri S. Likhachev (1907-1999), who some claim was once arrested by the KGB as a "counter-Revolutionary" for using the ъ.
After the fall of the Soviet Union, people began looking for symbols to replace those of the Communist era. The old tsarist two-headed eagle was readopted as the symbol of the Russian state, as was the old "white, blue and red" flag. Some people also began taking up Likhachev's cause and using the purged ъ as a letter and "symbol" - something about the former stability. Indeed, one of the leading financial publications of Russia is called КоммерсантЪ, also known by the symbol Ъ - which is pronounced "твердый знак."
Keep the faith,