Satan is real, an angel of darkess, a being with immense power; he is not merely a power or force, and moreover he has control over the whole world but he is not responsible for every evil or bad thing, although through tempting Eve sin entered the world (Romans 5:12, 1 Timothy 2:14). We know this because the Bible says so.
Firstly Jesus Christ teaches about Satan, for example, Jesus speaking of him says:
Now is the judgment of this world; now the ruler of this world will be cast out. (John 12:31 NKJV)
Secondly every New Testament writer mentions him; Satan is mentioned in 19 out of the 27 New Testament books. In the following case, Paul wanted to visit a church to encourage them, but Satan prevented it. This is a typical action of Satan who does not what functional churches, especially those that evangelise. In the case of the church at Thessalonica, Paul needed to deal with false doctrine that was causing much anxiety.
Therefore we wanted to come to you - even I, Paul, time and again - but Satan hindered us. (1 Thessalonians 2:18 NKJV)
However, it is the Old Testament where we find how Satan came to be, and the breadth of his dominion. Satan (or the Devil) is first mention in Genesis and therefore not confined to prophetic books; he is mentioned in historical narrative, wisdom and prophetic writings. His ending is described in detail in The Revelation, which describes the use of Hell, which was prepared for Satan and his angels.
Now when the thousand years have expired, Satan will be released from his prison … The devil, who deceived them, was cast into the lake of fire and brimstone where the beast and the false prophet are. And they will be tormented day and night forever and ever. (Revelation 20:7-10 NKJV)
Satan was created by God, not as an evil deceiver of the world, but the highest ranking angel – a cherub. Satan and his followers were all angels – spirit beings that cannot die. Their duty was to glorify God and carry out His pleasure in governance of the universe – and earth in particular. God created each being according to His counsels such that various orders existed; some over others, some beneath others, with roles, intelligence and other attributes suitable for their role. In the case of Satan, who was an angel – was the most beautiful and wisest of them all:
Moreover the word of the LORD came to me, saying, "Son of man, take up a lamentation for the king of Tyre, and say to him, 'Thus says the Lord GOD: "You were the seal of perfection, Full of wisdom and perfect in beauty. You were in Eden, the garden of God; Every precious stone was your covering: The sardius, topaz, and diamond, Beryl, onyx, and jasper, Sapphire, turquoise, and emerald with gold. The workmanship of your timbrels and pipes Was prepared for you on the day you were created. "You were the anointed cherub who covers; I established you; You were on the holy mountain of God; You walked back and forth in the midst of fiery stones. You were perfect in your ways from the day you were created, Till iniquity was found in you. (Ezekiel 28:11-15 NKJV)
This verse uses metaphors that show that God created Satan and his role was that of chief worshipper of God, an anointed cherubim (singular of cherub) – standing next to the throne leading all other beings in worship of Him. Ezekiel chapter 10 expands a little on cherubim and shows their actions supporting the throne of God. Note that God created Satan meaning he has not existed for all time but rather he was created in utmost beauty – "the seal of perfection", meaning, that all he had was full of perfection, and furthermore, he was perfect on creation, and therefore had no flaws.
Satan fell; indeed he was the first fallen creature in the universe, and he sinned right from the beginning: the devil has sinned from the beginning (1 John 3:8b). The reason he fell was due to his pride. Paul uses the example of Satan as a reminder of what pride does to a person.
not a novice, lest being puffed up with pride he fall into the same condemnation as the devil. 1 Timothy 3:6
The fall of Statan due to what he did and is called sin. Some has suggested, and I agree, that the passage of Ezekiel sets out the origin of unrighteousness, called sin;
"By the abundance of your trading You became filled with violence within, And you sinned; Therefore I cast you as a profane thing Out of the mountain of God; And I destroyed you, O covering cherub, From the midst of the fiery stones." Ezekiel 28:16
Again we see 'picture language'. Satan due to his pride attempted to userp God, and was precluded from being the worship leader of the Throne of God ("the mountain of God"), by being removed from the office of high priest in Heaven (the position that led worship). Furthermore, God destroyed him by preventing absolute control of earth. To understand this part of the verse we need to realise the original earth was covered with precious stones, diamonds, sapphires etc. all of which require enomous heat to be producted, hence the metaphore "fiery stones" to describe them. (We will see the same in the eternal Kingdom, which is described in Isaiah 54:11-17, which Jeremiah elaborates upon, speaking of the Throne of God (3:16-18)).
Satan is given four names in the Bible, the most common being Satan, meaning adversary or the one who resists. He is call the Devil, meaning "accuser" or "slander", that is, the one "who trips up". The Hebrews used the name Beelzebub (or Beel Zebub), meaning "lord of the flies", and was the god of Ekron (2 Kings 1:2 etc). We see this name being used in the Gospels, such as when Jesus is speaking to Jews (e.g. Matthew 10:25), or when the Jewish rulers state Jesus is from Satan (Beelzebub) – Matthew 12, Mark 3 & Luke 11. Paul uses the term Belial to describe Satan, meaning "worthlessness" or "recklessness" (2 Corinthians 6:15).
To emphasise the role, power and unrighteousness of Satan the Bible ascribes him various titles. He is the shining one, related to the elevation and magnificence of his creation. Bibles render the Hebrew in different ways, but day or morning -star is the most descriptive (Isaiah 14:12). Arnold Fruchtenbaum indicates the correct title is "day-star, son of the morning" – because "Lucifer" is a proper noun, not a title; and a title is being indicated in this passage.
Since he has set about destroying the souls of men and the relationship between God and His creation, he is called the destroyer (Revelation 9:11).
John views Satan in opposition to God as the prince (or ruler) of this world (John 12:31, 14:30 & 16:11). As the prince of the world (cosmos in Greek, thus the realm is greater than planet earth), he opposes the Prince of the Kingdom of God, the title of the Son of God, the Messiah. In everything Satan attempts to emulate the Messiah deceptively, and thus has an extremely extensive counterfeit program
Now is the judgment of this world; now the ruler (prince) of this world will be cast out. John 12:31
In relation to the cosmos, Satan is the ruler (or prince) of the powers of the air, which describes another of his abodes – the atmosphere above us. This title also indicates he has power over the other fallen angels, who have various powers, and live in the atmosphere;
you once walked according to the course of this world, according to the prince of the power of the air, the spirit who now works in the sons of disobedience Ephesians 2:2
A similar term is used by the Jews who describes Satan as the prince of demons. (Matthew 12:24, Luke 11:15), where the demons are the angels that fell with Satan.
Give Satan's power and influence on earth, Paul describes Satan as the god of this age (2 Corinthians 4:4), where the word 'age' (Greek aion) epitamises the current philosophies of man, which blinds people to the truth.
Satan is plainly the evil (or corrupt) one a title used by Jesus and recorded in Matthew 6:13 and John 17:15.
Satan is also given titles that correlate with various corrupt kingdoms. Ezekiel refers to him as the king of Tyre (Ezekiel 28:11-12) and Isaiah as the king of Babylon (Isaiah 14:4) which shows his control over kingdoms and nations.
Satan is not just a force or power. Satan is an intelligent being, who can speak, deceive (as in Genesis 3), debate (as in Job), and has emotion (is puffed up, as described by Paul in 1 Timothy 3:6). He has a will to the extent that he can give any nation to whom he wills (Luke 4:6-7), and he walks around seeking whom he may devour (1 Peter 5:8). Note also in the orginal language, Hebrew, that described Satan, he is always refered to using the pronoun "he", "him" or "his". It is never "it".
The Bible also treats Satan as a morally responsible person. God can do this because Satan has the capacity to reason and has a will, therefore can make choices. His unrighteousness therefore is judged, as any other morally responsible person is.
the ruler [prince or Satan] of this world is judged. John 16:11
The consequence is already known, and spoken of by Jesus, recorded by Matthew.
"Then He will also say to those on the left hand, 'Depart from Me, you cursed, into the everlasting fire prepared for the devil and his angels: Matthew 25:41
In summary, Satan is a being, a fallen angel that has control of this world (for a time) mainly through deception, and attacks believers, in particular. Believers have access to a range of defences to deal with him, and must avail themselves of these. What a believer needs to comprehend is Satan does not have unfettered power; God has restrained him (See the first two chapters of Job) and God has given believers defences, with the Holy Spirit being the most important. In the end Satan will be judged and along with his angels will be thrown into hell, for all enternity.
 Don't be put off by changes in vowels in words. Some spell this name Ballzebub. Vowels are very geo-centric. They change across a continent. On the other hand consonants are don't change.
 Note that the King James Version renders day or morning-star as "Lucifer".