Hi, great question!
Ionic compounds are compounds that are made up of ions. That is, where the name comes from. Ionic compounds, however, can be explained a little better so as to differentiate them between the main other type, covalent compounds.

Ionic compounds, have ions, which do not share electrons. That means that if you have a compound like NaCl (table salt), the sodium is missing one electron and is, positively charged (Na+), and the chlorine has one extra electron, and is negatively charged (Cl-). The positive and negative attract, balancing each other out, making a stable compound.

Ionic compounds are compounds where one atom or group of atoms (the cation) releases an electron that is then taken up by another atom or group of atoms (the anion). The compound is then held together by electrostatic force of opposite charges attracting. This is different from a covalent compound in that covalent compounds place electrons into new energy states that are not simply one atom losing an electron and the other gaining one. The reason why being ionic is important is that the ions can get broken apart by interacting with the positive and negative ends of polar, but covalently-bonded molecules such as water, which is why salts in general dissolve so readily in water.

Ionic compounds are compounds that have positive ions and negative ions The ions separate when the ionic compound is dissolved in water. Table salt is a good example. It is NaCl. But the Na takes a proton from the Cl, and 2 ions are formed: Na+ and Cl-. These ions separate when you put the salt in water.

In contrast, sugar is not an ionic compound, so when you dissolve it in water, it stays as the same sugar molecules that were in the dry sugar crystal.

Ionic compounds are compounds (substances made of more than one type of atoms, so sodium is not a compound, but sodium chloride, otherwise known as table salt, is a compound) made of ions. Ions come from atoms - either single atoms, or a group of atoms linked together - that have either lost electrons or gained electrons.

Electrons are particles that make up atoms, and can be exchanged. Each electron carries a single negative charge, so atoms that lose electrons become positively charged, and atoms that gain electrons become negatively charged. These are no longer called atoms; they are now ions that are called cations (ions with positive charges) and anions (ions with negative charges), respectively. Ionic compounds are made of these ions. Because these ions have electrical charges, the cations and anions are attracted to each other (opposite charges attract), and these compounds in their solid forms are held together as very small crystals by the attractive forces exerted by the ions on each other.