diff --git a/LectureNote-data,string.py b/LectureNote-data,string.py
new file mode 100644
index 0000000000000000000000000000000000000000..20fd8b9aa1b9df412c50513d450d3631a73ab06a
--- /dev/null
+++ b/LectureNote-data,string.py
@@ -0,0 +1,195 @@
+Python 3.7.1 (v3.7.1:260ec2c36a, Oct 20 2018, 03:13:28) 
+[Clang 6.0 (clang-600.0.57)] on darwin
+Type "help", "copyright", "credits" or "license()" for more information.
+>>> b=22/7
+>>> b
+3.142857142857143
+>>> type(b)
+<class 'float'>
+>>> # 부동소수형의 사칙 연산
+>>> a=1.23 +0.32
+>>> a
+1.55
+>>> b= 3.0 -1.5
+>>> b
+1.5
+>>> c= 2.1 *2.0
+>>> c
+4.2
+>>> d=4.5//2.0
+>>> d
+2.0
+>>> e=4.5%2.0
+>>> e
+0.5
+>>> f= 4.5/2.0
+>>> f
+2.25
+>>> #복소수
+>>> a = 2+3j
+>>> a
+(2+3j)
+>>> type(a)
+<class 'complex'>
+>>> a.real
+2.0
+>>> a.imag
+3.0
+>>> a.conjugate()
+(2-3j)
+>>> #math모듈 사용
+>>> import math
+>>> math.pi
+3.141592653589793
+>>> math.e
+2.718281828459045
+>>> trunc(1.6)
+Traceback (most recent call last):
+  File "<pyshell#27>", line 1, in <module>
+    trunc(1.6)
+NameError: name 'trunc' is not defined
+>>> math.trunc(1.6)
+1
+>>> abs(-123)
+123
+>>> round(1.4)
+1
+>>> round(1.5)
+2
+>>> math.factorial(10)
+3628800
+>>> math.factorial(100)
+93326215443944152681699238856266700490715968264381621468592963895217599993229915608941463976156518286253697920827223758251185210916864000000000000000000000000
+>>> #파이썬은 메모리 허용범위내에서 정수를 무한히 찍어낼수있다.
+>>> 3**3
+27
+>>> math.pow(3,3)
+27.0
+>>> math.sqrt(81)
+9.0
+>>> math.log(4,2)
+2.0
+>>> math.log(81,3)
+4.0
+>>> math.log10(1000)
+3.0
+>>> math.log(math.e)
+1.0
+>>> #텍스트 다루기
+>>> a='hello,world.'
+>>> a
+'hello,world.'
+>>> b="안녕하세요"
+>>> b
+'안녕하세요'
+>>> c='''hello
+welcome
+java '''
+>>> c
+'hello\nwelcome\njava '
+>>> d=""" hello
+welcome
+python"""
+>>> d
+' hello\nwelcome\npython'
+>>> type(d)
+<class 'str'>
+>>> e=a+b
+>>> e
+'hello,world.안녕하세요'
+>>> a[0:2]
+'he'
+>>> 'hel'in a
+True
+>>> x in a
+Traceback (most recent call last):
+  File "<pyshell#60>", line 1, in <module>
+    x in a
+NameError: name 'x' is not defined
+>>> 'x' in a
+False
+>>> len(a)
+12
+>>> len(b)
+5
+>>> #문자열 메소드
+>>> a = 'hello'
+>>> a.startwith('h')
+Traceback (most recent call last):
+  File "<pyshell#66>", line 1, in <module>
+    a.startwith('h')
+AttributeError: 'str' object has no attribute 'startwith'
+>>> a.startswith('h')
+True
+>>> a.startswith('e')
+False
+>>> a.endswith('h')
+False
+>>> a.endswith('o')
+True
+>>> a.fine('hel')
+Traceback (most recent call last):
+  File "<pyshell#71>", line 1, in <module>
+    a.fine('hel')
+AttributeError: 'str' object has no attribute 'fine'
+>>> a.find('hel')
+0
+>>> a.find('ll')
+2
+>>> a.fine('x')
+Traceback (most recent call last):
+  File "<pyshell#74>", line 1, in <module>
+    a.fine('x')
+AttributeError: 'str' object has no attribute 'fine'
+>>> a.find('x')
+-1
+>>> a.count('l')
+2
+>>> a='apple,orange,kiwi'
+>>> b=a.split(',')
+>>> b
+['apple', 'orange', 'kiwi']
+>>> type(b)
+<class 'list'>
+>>> b[0]
+'apple'
+>>> b[1]
+'orange'
+>>> b[2]
+'kiwi'
+>>> a=input()
+b=input()
+>>> resule= a*b
+Traceback (most recent call last):
+  File "<pyshell#85>", line 1, in <module>
+    resule= a*b
+TypeError: can't multiply sequence by non-int of type 'list'
+>>> #문자열을 숫자로 바꾸기
+>>> int('1234567890')
+1234567890
+>>> float('123.4567')
+123.4567
+>>> complex('1+2j')
+(1+2j)
+>>> print("첫수를 입력하시오 : ")
+첫수를 입력하시오 : 
+>>> 
+=========== RESTART: /Users/kimminsub/Documents/input_multiply.py ===========
+첫번째 수를 입력하시오: 
+5
+두번째 수를 입력하시오: 
+4
+5 * 4 = 20 
+>>> type(math.pi)
+Traceback (most recent call last):
+  File "<pyshell#91>", line 1, in <module>
+    type(math.pi)
+NameError: name 'math' is not defined
+>>> import math
+>>> type(math.pi)
+<class 'float'>
+>>> str(math.pi)
+'3.141592653589793'
+>>> type(math.pi)
+<class 'float'>
+>>>