What Is Score Bits In Blast?

i want to konw that what does it mean score and bits in local blast output from the following example?'.

Score = 38.2 bits (19), Expect = 0.11
 Identities = 22/23 (95%)



Query: 1      cttaacttcagctacctcgagta 23
          <br>|||||||||||||||||| ||||<br>
Sbjct: 732552 cttaacttcagctacctccagta 732574