# Display the user and group ids of your current user.id# Display the last users who have logged onto the system.last# Show who is logged into the system.who# Show who is logged in and what they are doing.w# Create a group named "test".groupadd test# Create an account named john, with a comment of "

# Display and manage the top processestop# Interactive process viewer (top alternative)htop# Display processor related statisticsmpstat 1# Display virtual memory statisticsvmstat 1# Display I/O statisticsiostat 1# Display the last 100 syslog messages  (Use /var/log/syslog for Debian based syste

# Display messages in kernel ring bufferdmesg# Display CPU informationcat /proc/cpuinfo# Display memory informationcat /proc/meminfo# Display free and used memory ( -h for human readable, -m for MB, -g for GB.)free -h# Display PCI deviceslspci -tv# Display USB deviceslsusb -tv# Display DMI/SMBIOS (h

# Display Linux system informationuname -a# Display kernel release informationuname -r# Show operating system information such as distribution name and versioncat /etc/os-release# Show how long the system has been running + loaduptime# Show system host namehostname# Display all local IP addresses of

//  Program to explain Generic Interfaces.interface MinMax<T extends Comparable<T>> {T min();T max();}class MyClass<T extends Comparable<T>> implements MinMax<T> {T[ ] vals;MyClass(T[ ] o) { vals = o;}public T min() { T v = vals[0

//  Program to explain that a subclass can add its own type parameters.class  Gen<T> {T ob;Gen(T o) { ob = o;}T getob() { return ob;}}class  Gen2<T, V> extends Gen<T> {V ob2;Gen2(T o, V o2) { super(o); ob2 = o2;}V getob2()

// Program to explain Overriding Methods in a Generic Class.class  Gen<T> { T ob; Gen(T o) {  ob = o; } T getObject() {  System.out.println("Gen's getObject(): " ); return ob; } }class Gen2<T> extends  Gen<

// Program to explain that the Non-generic class can be // the Super class of a Generic subclass.class  NonGen {int num;NonGen(int i) { num = i;}int getNumber() { return num;}}class  Gen<T> extends  NonGen { T ob;   Gen(T o,