There were four altogether, and it is easy to be confused.* One was the father of the apostle Judas (not Iscariot), and nothing more is known of him.—Luke 6:16; Acts 1:13.
Then we have a son of Zebedee. This James was brother of John, both being Jesus’ apostles. (Matthew 10:2) His mother, it seems, was Salome, the sister of Jesus’ mother. (Compare Matthew 27:55, 56 with Mark 15:40, 41 and John 19:25.) If so, James was Jesus’ first cousin. He was a fisherman, who along with his brother was in partnership with Peter and Andrew.—Mark 1:16-19; Luke 5:7-10.
Next comes James the son of Alphaeus, also one of Jesus’ apostles. (Mark 3:16-18) He is described as “James the Less” at Mark 15:40. He may have been called “the Less” because of being physically smaller or younger than James, the son of Zebedee.
Last comes Joseph and Mary’s son, brother of Jude and half brother of Jesus. (Mark 6:3; Galatians 1:19) During Jesus’ ministry, James was not one of his disciples. (Matthew 12:46-50; John 7:5) However, before Pentecost 33 C.E., James prayed with his mother, his brothers, and the apostles in an upper chamber in Jerusalem. (Acts 1:13, 14) James later became a prominent member of the Jerusalem congregation and wrote the Bible book bearing his name.—Acts 12:17; James 1:1.
James is the English equivalent of Jacob. The phrase “Abraham, Isaac and Jacob” appears many times in the Bible, and Matthew 1:16 names Jacob as “father to Joseph the husband of Mary.”