diff --git a/class04/Cargo.lock b/class04/Cargo.lock
new file mode 100644
index 0000000..240ccb2
--- /dev/null
+++ b/class04/Cargo.lock
@@ -0,0 +1,6 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+[[package]]
+name = "class04"
+version = "0.1.0"
+
diff --git a/class04/Cargo.toml b/class04/Cargo.toml
new file mode 100644
index 0000000..453f7df
--- /dev/null
+++ b/class04/Cargo.toml
@@ -0,0 +1,9 @@
+[package]
+name = "class04"
+version = "0.1.0"
+authors = ["Admin <faheemuzzaman@hotmail.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
diff --git a/class04/src/main.rs b/class04/src/main.rs
new file mode 100644
index 0000000..2ac892c
--- /dev/null
+++ b/class04/src/main.rs
@@ -0,0 +1,42 @@
+// fn main() {
+//     let x  = 10;
+//     let y  = x;
+//     println!("{} ,{}",x,y);
+
+//     let s1 = String::from("Hello");
+//     let s2 = s1.clone();
+//     let s3 = &s1;
+
+//     let s4 = &s1;
+//     println!("{}, {}, {}, {}", s1, s2, s3, s4);
+// // }
+// fn main() {
+//     let s = String::from("hello"); 
+//     takes_ownership(s.clone()); 
+//     println!("{}",s);            
+//     let x = 5;                      
+//     makes_copy(x);                  
+// }
+// fn takes_ownership(some_string: String) {
+//     println!("{}", some_string);
+// } 
+// fn makes_copy(some_integer: i32) { 
+//     println!("{}", some_integer);
+// }
+
+fn main() {
+    let s1 = gives_ownership();
+    let s2 = String::from("hello");    
+    let s3 = takes_and_gives_back(s2);
+    println!("{}",s1);    
+        println!("{}",s3);        
+    
+
+}
+fn gives_ownership() -> String {            
+    let some_string = String::from("hello");
+    some_string                             
+}
+fn takes_and_gives_back(a_string: String) -> String { 
+    a_string  
+}
diff --git a/class04/target/.rustc_info.json b/class04/target/.rustc_info.json
new file mode 100644
index 0000000..0e1b595
--- /dev/null
+++ b/class04/target/.rustc_info.json
@@ -0,0 +1 @@
+{"rustc_fingerprint":9484594007537757877,"outputs":{"4476964694761187371":["___.exe\nlib___.rlib\n___.dll\n___.dll\n___.lib\n___.dll\nC:\\Users\\Admin\\.rustup\\toolchains\\stable-x86_64-pc-windows-msvc\ndebug_assertions\nproc_macro\ntarget_arch=\"x86_64\"\ntarget_endian=\"little\"\ntarget_env=\"msvc\"\ntarget_family=\"windows\"\ntarget_feature=\"fxsr\"\ntarget_feature=\"sse\"\ntarget_feature=\"sse2\"\ntarget_os=\"windows\"\ntarget_pointer_width=\"64\"\ntarget_vendor=\"pc\"\nwindows\n",""],"1164083562126845933":["rustc 1.37.0 (eae3437df 2019-08-13)\nbinary: rustc\ncommit-hash: eae3437dfe991621e8afdc82734f4a172d7ddf9b\ncommit-date: 2019-08-13\nhost: x86_64-pc-windows-msvc\nrelease: 1.37.0\nLLVM version: 8.0\n",""],"9311443727202421799":["___.exe\nlib___.rlib\n___.dll\n___.dll\n___.lib\n___.dll\nC:\\Users\\Admin\\.rustup\\toolchains\\stable-x86_64-pc-windows-msvc\ndebug_assertions\nproc_macro\ntarget_arch=\"x86_64\"\ntarget_endian=\"little\"\ntarget_env=\"msvc\"\ntarget_family=\"windows\"\ntarget_feature=\"fxsr\"\ntarget_feature=\"sse\"\ntarget_feature=\"sse2\"\ntarget_os=\"windows\"\ntarget_pointer_width=\"64\"\ntarget_vendor=\"pc\"\nwindows\n",""]},"successes":{}}
\ No newline at end of file
diff --git a/class04/target/debug/.cargo-lock b/class04/target/debug/.cargo-lock
new file mode 100644
index 0000000..e69de29
diff --git a/class04/target/debug/.fingerprint/class04-288ce7719697c293/dep-test-bin-class04-288ce7719697c293 b/class04/target/debug/.fingerprint/class04-288ce7719697c293/dep-test-bin-class04-288ce7719697c293
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index 0000000..f59c955
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diff --git a/class04/target/debug/.fingerprint/class04-288ce7719697c293/invoked.timestamp b/class04/target/debug/.fingerprint/class04-288ce7719697c293/invoked.timestamp
new file mode 100644
index 0000000..e00328d
--- /dev/null
+++ b/class04/target/debug/.fingerprint/class04-288ce7719697c293/invoked.timestamp
@@ -0,0 +1 @@
+This file has an mtime of when this was started.
\ No newline at end of file
diff --git a/class04/target/debug/.fingerprint/class04-288ce7719697c293/test-bin-class04-288ce7719697c293 b/class04/target/debug/.fingerprint/class04-288ce7719697c293/test-bin-class04-288ce7719697c293
new file mode 100644
index 0000000..837f115
--- /dev/null
+++ b/class04/target/debug/.fingerprint/class04-288ce7719697c293/test-bin-class04-288ce7719697c293
@@ -0,0 +1 @@
+d24ad2a210b2794b
\ No newline at end of file
diff --git a/class04/target/debug/.fingerprint/class04-288ce7719697c293/test-bin-class04-288ce7719697c293.json b/class04/target/debug/.fingerprint/class04-288ce7719697c293/test-bin-class04-288ce7719697c293.json
new file mode 100644
index 0000000..8a929d7
--- /dev/null
+++ b/class04/target/debug/.fingerprint/class04-288ce7719697c293/test-bin-class04-288ce7719697c293.json
@@ -0,0 +1 @@
+{"rustc":16761476351873615079,"features":"[]","target":457681104562150112,"profile":1647870076477133176,"path":1036222786711178230,"deps":[],"local":[{"CheckDepInfo":{"dep_info":".fingerprint\\class04-288ce7719697c293\\dep-test-bin-class04-288ce7719697c293"}}],"rustflags":[],"metadata":11626969923688510520}
\ No newline at end of file
diff --git a/class04/target/debug/.fingerprint/class04-e6cf225208f9f5ca/bin-class04-e6cf225208f9f5ca b/class04/target/debug/.fingerprint/class04-e6cf225208f9f5ca/bin-class04-e6cf225208f9f5ca
new file mode 100644
index 0000000..ee0f64b
--- /dev/null
+++ b/class04/target/debug/.fingerprint/class04-e6cf225208f9f5ca/bin-class04-e6cf225208f9f5ca
@@ -0,0 +1 @@
+42d6f14e3daced75
\ No newline at end of file
diff --git a/class04/target/debug/.fingerprint/class04-e6cf225208f9f5ca/bin-class04-e6cf225208f9f5ca.json b/class04/target/debug/.fingerprint/class04-e6cf225208f9f5ca/bin-class04-e6cf225208f9f5ca.json
new file mode 100644
index 0000000..07a64c5
--- /dev/null
+++ b/class04/target/debug/.fingerprint/class04-e6cf225208f9f5ca/bin-class04-e6cf225208f9f5ca.json
@@ -0,0 +1 @@
+{"rustc":16761476351873615079,"features":"[]","target":457681104562150112,"profile":14891217944882224483,"path":1036222786711178230,"deps":[],"local":[{"CheckDepInfo":{"dep_info":".fingerprint\\class04-e6cf225208f9f5ca\\dep-bin-class04-e6cf225208f9f5ca"}}],"rustflags":[],"metadata":11626969923688510520}
\ No newline at end of file
diff --git a/class04/target/debug/.fingerprint/class04-e6cf225208f9f5ca/dep-bin-class04-e6cf225208f9f5ca b/class04/target/debug/.fingerprint/class04-e6cf225208f9f5ca/dep-bin-class04-e6cf225208f9f5ca
new file mode 100644
index 0000000..f59c955
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diff --git a/class04/target/debug/.fingerprint/class04-e6cf225208f9f5ca/invoked.timestamp b/class04/target/debug/.fingerprint/class04-e6cf225208f9f5ca/invoked.timestamp
new file mode 100644
index 0000000..e00328d
--- /dev/null
+++ b/class04/target/debug/.fingerprint/class04-e6cf225208f9f5ca/invoked.timestamp
@@ -0,0 +1 @@
+This file has an mtime of when this was started.
\ No newline at end of file
diff --git a/class04/target/debug/deps/class04-288ce7719697c293.d b/class04/target/debug/deps/class04-288ce7719697c293.d
new file mode 100644
index 0000000..36c7a83
--- /dev/null
+++ b/class04/target/debug/deps/class04-288ce7719697c293.d
@@ -0,0 +1,5 @@
+c:\Users\Admin\Desktop\Rust\class04\target\debug\deps\class04-288ce7719697c293.rmeta: src\main.rs
+
+c:\Users\Admin\Desktop\Rust\class04\target\debug\deps\class04-288ce7719697c293.d: src\main.rs
+
+src\main.rs:
diff --git a/class04/target/debug/deps/class04-e6cf225208f9f5ca.d b/class04/target/debug/deps/class04-e6cf225208f9f5ca.d
new file mode 100644
index 0000000..d5df675
--- /dev/null
+++ b/class04/target/debug/deps/class04-e6cf225208f9f5ca.d
@@ -0,0 +1,5 @@
+c:\Users\Admin\Desktop\Rust\class04\target\debug\deps\class04-e6cf225208f9f5ca.rmeta: src\main.rs
+
+c:\Users\Admin\Desktop\Rust\class04\target\debug\deps\class04-e6cf225208f9f5ca.d: src\main.rs
+
+src\main.rs:
diff --git a/class04/target/debug/deps/libclass04-288ce7719697c293.rmeta b/class04/target/debug/deps/libclass04-288ce7719697c293.rmeta
new file mode 100644
index 0000000..e69de29
diff --git a/class04/target/debug/deps/libclass04-e6cf225208f9f5ca.rmeta b/class04/target/debug/deps/libclass04-e6cf225208f9f5ca.rmeta
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index 0000000..e69de29
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