This time signature is called the three four time signature. It tells you there are three beats in each bar. Three four time is also known as waltz time. There are three quarter notes in one bar of ^ time.
A dot written after a note extends its value by half. A dot after a half note means that you hold it for three beats. One dotted half note makes one bar of music in ^ time.
This song is in ^ time and contains dotted half notes.
The next song contains two curved lines called slurs. A slur indicates that the notes written above or below it should be played legato. Legato means to play the notes smoothly, so that they sound connected to each other.
To play notes legato, keep your finger on the key until you have started to play the next key.
This song contains dotted half notes and is played legato.
A dot placed above or below a note tells you to play it staccato. Staccato means to play a note short and separate from the other notes.
To play a note short, lift your finger off the keys as quickly as possible.
This song has a lead-in in ^ time and uses staccato notes.