Note taking in EGR115. notebook slide number in margin. comments on the right. write down vocabulary words write down overall ideas write down things that we repeat 4 or 5 times! write down possible errors printout of slides print 2 or 3 slides per page draw arrows, add your comments
History of computers (4 slides)
What is a computer system?
What is software?
What is programming?
Compiled vs. interpreted
Computers ≠ calculators
Computers are programmable. The first calculators were not programmable, hence not considered computers.
Babbage’s difference engine
Device to subtract adjacent valuesin a column of numbers. Created for engineers in charge of creating tables of logarithms and trigonometric functions.
Primarily used for breaking the German codes during World War 2.
It would crack Enigma Codes (codes that were cracked by exhaustively shifting text by arbitrary amounts). For example:
‘Zsszbjzs 9599’ would be
‘Attack at 0600’
CPU + memory
( ) ‘ ’ , ;
if for else while switch case otherwise end input fprintf
1) Machine language – also
called binary language.
Sequence of 0’s and 1’s.
2) Assembly language – each line of code produces a single machine instruction (add, subtract…)
3) High-level language – slightly closer to spoken languages.
a= a + b + c;
This line does the same as the two above.