Thanks for the compliments!

I can help with explaining:

TTL = Transistor to Transistor Logic

IC= Integrated Circuit = Chip (more or less in a loose translation) = simple form of electronic building blocks

Being European, you might have had a Logic Class at some point, in the US they've substituted a course in Euclidean Geometry at the High School level for Traditional Logic in the curriculum.

The most simple TTL chip I saw on your board in a quick viewing was a 7408 with some "abracadabra" thrown into the name.

It's actually four simple logical operation circuits made of transistors that can be used, individually, tied together with traces (printed circuit board "wires") or in combinations with other Chips to create a more complicated logical operator.

The logical operation of all four circuits on this chip is "AND":

each consists of two input connections and one output connection.

IF either input is A (called Low) THEN the output is A low, so:

IF input 1 is A AND input 2 is neutral THEN output = A Low

IF input 1 is neutral AND input 2 is A THEN output = A Low

IFboth inputs are B (called high) THEN the output is B high,

Sorry, that's the best I can do in the time available, I hope I got it right. Gotta run!