Here are five of the most important things to know.
Although the country is not fighting any full-scale wars at the moment, there is the ever-present danger that fresh conflict will erupt with its regional foes.
"Gantz and Lapid will be sitting here tomorrow", Prime Minister Benjamin Netanyahu warned on Facebook as he sat in the Prime Minister's Residence in Jerusalem with some confidants and an American adviser, who were all warning of "indifference" and low voter turnout in various locations where Netanyahu's Likud party should be doing well, they said. Without a parliamentary majority, Netanyahu dissolved parliament and called a new election.
The fate of the Palestinians depends on who is in power in Israel, since Israel occupies land which they seek for a state of their own.
Several polling stations in Israel were closed temporarily because of various illegal activity, officials said.
The Trump administration plans soon to release an Israeli-Palestinian peace plan that may prove a dead letter: The Palestinians have rejected it in advance as biased.
A substantial Arab turnout could hurt Netanyahu's hopes for another term. Gantz promises little to no change on issues like defense, diplomacy or economics. Gantz has tried to capitalize on a series of corruption investigations. The central question on the agenda was ostensibly simple: Should Netanyahu be elected to another term after ten consecutive years in office?
'We're working with elections officials around the world to help ensure the integrity of the elections, ' the company told the Times of Israel. Neither managed to attract enough smaller parties to reach the bare minimum of 61 seats needed for a government, however, as conflict between the ultra-religious Haredim and the nationalist settlers scuttled coalition talks. Campaigning on rhetoric of unity and egalitarianism, Gantz says he represents a fresh start for Israel and has ruled out joining forces with a prime minister accused of serious crimes.
Dubbed "King Bibi" by his supporters, Netanyahu, 69, had already been stung by his failure to form a government after an election on April. Their exemptions are a sore point with many secular Israelis.
With a hoarse voice and appearing haggard after days of intense campaigning, Netanyahu appeared before supporters in the early hours of Wednesday and said he was prepared for negotiations to form a "strong Zionist government".
German Chancellor Angela Merkel, right, and Jordan's King Abdullah II, left, address the media during a joint press conference after a meeting at the Chancellery in Berlin, Germany, Tuesday, Sept. 17, 2019.
That has led to a degree of voter fatigue, which could depress turnout.
There have also been multiple reports of polling irregularities.
Apart from Mr Netanyahu and Mr Gantz, a key figure to watch is Mr Avigdor Liberman of the right-wing Yisrael Beitenu party. The following month, the coalition collapsed.
Blue and White party, led by Benny Gantz, has said they have no objection to forming a unity government with the Likud but without Netanyahu as it's leader.
In April's vote, the justice and education ministers at the time, Ayelet Shaked and Naftali Bennett, broke away from their Jewish Home party to run independently. The grouping's performance will be crucial to Mr Netanyahu's ability to put together a governing coalition.
When it comes to security issues, the political differences between Likud and Blue and White are narrow, with both sides taking a similarly hard line on the regional struggle against Iran and relations with the Palestinians.