List<Account> accounts = new List<Account>{
    new Account(Name = 'Foo', AnnualRevenue = 50000),
    new Account(Name = 'Bar', AnnualRevenue = 30000)
}

Collection accountCollection = Collection.of(accounts);

Collection filtered = accountCollection.filter(Match.field(Account.AnnualRevenue).greaterThan(40000));
Collection mapped = filtered.mapAll(Transform.record(new Account(High_Value__c = true)));
Collection remaining = mapped.remove(Match.record(new Account(Name = 'Bar')));

Collection accountCollection = Collection.of(accounts);

Account prototype = new Account(Name = 'Foo');
Collection recordMatched = accountCollection.filter(Match.record(prototype));

Collection fieldMatched = accountCollection.filter(Match.field(Account.Name).equals('Foo'));

FieldsMatch m = Match.field(Account.Name).equals('Foo').also(Account.AnnualRevenue).greaterThan(100000);

Collection filtered = Collection.of(accounts).filter(Match.field(Account.Name).equals('Foo').also(Account.AnnualRevenue).greaterThan(100000));

Account prototype = new Account(
    Name = 'Test',
    AnnualRevenue = 50000000
);
// Accounts named 'Test' with an AnnualRevenue of **exactly** 50,000,000 are matched
Collection filtered = accountCollection.filter(Match.record(prototype));

List<Account> accounts = new List<Account>{
	new Account(Name = 'Foo'),
	new Account(Name = 'Bar')
}
// Names are plucked into a new list, ['Foo', 'Bar']
List<String> names = Collection.of(accounts).pluckStrings(Account.Name);

List<Opportunity> opportunities = new List<Opportunity>{
	new Opportunity(Account = new Account(Name = 'Foo')),
	new Opportunity(Account = new Account(Name = 'Bar'))
};

// Names are plucked into a new list ['Foo', 'Bar']
List<String> accountNames = Collection.of(opportunities).pluckStrings('Account.Name');

Map<Date, List<Opportunity>> opportunitiesByCloseDate = Collection.of(opportunities).groupByDates(Opportunity.CloseDate, opportunities);

List<Opportunity> opportunities = new List<Opportunity>{
	new Opportunity(Name = 'Foo', Amount = 10000, Description = 'Bar')
}
// Picked contains just Name and Amount fields. Description is not present.
Collection picked = Collection.of(opportunities).pick(new Set<String>{'Name', 'Amount'});

private class DoubleAmount implements SObjectToSObjectFunction {
    public SObject apply(SObject record) {
        record.put('Amount', 2 * (Decimal) record.get('Amount'));
        return record;
    }
}

List<Opportunity> opps = new List<Opportunity>{
    new Opportunity(Amount = 100),
    new Opportunity(Amount = 150)
};

Collection.of(opps).mapAll(new DoubleAmount()); // amounts have been doubled

Collection.of(opps).mapAll(Transform.record(new Opportunity(Name = 'Test'))); // Name field has been overwritten with 'Test'

private class DoubleAmount implements SObjectToSObjectFunction {
    public SObject apply(SObject record) {
        record.put('Amount', 2 * (Decimal) record.get('Amount'));
        return record;
    }
}

List<Opportunity> opps = new List<Opportunity>{
    new Opportunity(Amount = 100),
    new Opportunity(Amount = 150)
};

Collection.of(opps).mapSome(Match.field('Amount').gt(120), new DoubleAmount()); // 100 remains, but 150 has been doubled to 300

List<SObject> objects = new List<SObject>();
List<Account> accounts = objects; // compiles!

List<Account> accounts = new List<Account>();
List<SObject> objects = accounts; // compiles as well!

List<SObject> objects = new List<SObject>();
System.debug(objects instanceof List<Account>); // true
System.debug(objects instanceof List<Opportunity>); // true

List<Account> filteredAccounts = accountCollection.asList();
// List<SObject> returned!

List<Account> filteredAccounts = accountCollection.asList(List<Account>.class);
// List<Account> returned!